Scalar Energy

Quantum Science, Scalar Energy Pendant, Nikola Tesla & More

July 7, 2015
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Nick Krygios is becoming the most hated man in tennis – His Monday press …

Q: Nick, can you give a proper explanation about why you didn’t return those serves? Looked like you were tanking the set. A proper explanation please.

Nick Kyrgios: What’s the question?

Q: Looked like you weren’t returning those serves. Looked like you weren’t trying, which is very unusual at Wimbledon.

Nick Kyrgios: Do you want to try and return Richard Gasquet’s serve? I’ll give you the racquet and we’ll see how many times you can return his serve.

Q: But you’re a professional tennis player, I’m not.

(Getty Images)

(Getty Images)

A defensive and defiant Nick Kyrgios sat in front of the media on Monday after his controversial four-set loss to Richard Gasquet at Wimbledon and snidely answered questions about his tanking of a game second set, fooling no one in insisting that he “did move” to return serve. (Yeah, right. The last time there were so many tanks in London, Eisenhower was getting ready to send them to Normandy.) The press conference continued Krygios down a path that is becoming more defined every time he takes the court or speaks to the media: Despite being just 20 years old and exactly one year from his debut as a big-time player, Nick Kyrgios is the most hated man in tennis. He also might be its future.

Here’s Monday’s contentious tank job, which occurred as Kyrgios was in the midst of dropping the first two sets to the higher-ranked Gasquet.

That was blatant and obvious. But how bad was it for Kyrgios or the sport? Well, we’ll get to that. But first, let’s acknowledge how tennis needs some new, boiling blood and Kyrgios is certainly up for the task. The fiery Greek-Aussie keeps a running on-court dialogue that sounds like the script to a Scorsese movie; he engages with fans mid-match; he hugs ballboys; he’s brash when he wins, obstinate when he loses and, as you can see, he already has a fine relationship with the press. He’s entertainment in a gold chain and bad haircut.

Screen Shot 2015-07-06 at 9.50.48 PM

Q: So you’re not denying that you stopped for that game?

Nick Kyrgios: Denying what?

Q: You’re denying that you stopped playing for that game.

Nick Kyrgios: I kept playing.

Q: For that moment, you weren’t returning.

Nick Kyrgios: And that’s coming from you? That’s your opinion.

(AP)

(AP)

You can chalk up his antics nd answers to being 20 years old. (Think about what you were doing when you were 20.) You can also say the interviewers were pressing a little too hard — Kyrgios clearly wasn’t going to tell the truth about tanking that game, so let it go. This is Wimbledon, not the magistrate’s court.

Frankly, I don’t mind the theoretical tanking either. Sometimes, if you’re down 0-40 on your opponent’s serve, it can make sense to tank a point and save energy before getting back on your serve. And anyway, even if you disagree with that, Kyrgios came back to win the third set and had two set points in a fourth-set tiebreak to push the match to a decisive fifth set. Tanking a few points clearly had no effect on the young Aussie. That’s been way overblown. It’s the brazen way Kyrgios does it though, making a mockery of the game and turning what he thinks is swagger into being a self-serving showboat.

(Getty Images)

(Getty Images)

But I love Kyrgios. For as great as tennis has been over the past decade — perhaps its best run in history, at least on the men’s side — the players have been vanilla. The only drama is in the matches, which thankfully have provided plenty of it. Except for the occasional eye roll or snide remark, you can count on one hand the number of times The Big Three has gotten truly testy with a chair umpire or been rude to the media. And all that effort on those 0-40 points, the lack of which Kyrgios is being eviscerated for today — that’s from those same players, who never are at any point in a game they don’t think they can win. That’s great for the sport too, but the pendulum has to swing back every now and then. A little controversy never hurt anybody.

(EPA)

(EPA)

Q: Do you think the crowd misjudged you when they started booing? Because I heard the booing from the crowd.

Nick Kyrgios: Yeah, and then I started playing well and they started cheering. Did you hear that too?

Q: Yes, but it’s so rare to hear that around —

Nick Kyrgios: (Interrupting and sarcastically) Okay, that okay. No, that’s okay.

A: Wimbledon.

(EPA)

(EPA)

There’s a fine line Kyrgios is walking here and the danger is following in the same footsteps as fellow countryman Bernard Tomic. Because the press and fans will put up with the antics as long as the on-court success backs it up. But if Kyrgios’s game falls off, like Tomic’s, or the headlines become increasingly more for what he says rather than what he does, suddenly the brashness of youth becomes the petulance of a falling star.

For now, Nick Kyrgios can get away with it, because when you’re controversial, you’re interesting too, and “the most interesting man in sport” has a nicer ring than “the most hated man in tennis.” So stay thirsty, Nick. Keep being a breath of fresh air. Just don’t let it get stale.

(Getty Images)

(Getty Images)

July 7, 2015
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The Basic Science Behind Creating Colors

The last couple of weeks of the science blogosphere have seen two really excellent posts about light-emitting things. First, Rhett Allain did a post on Illumination of Life: The Four Ways Humans Make Light, then Hillary Brueck here at Forbes explained the chemical elements responsible for the colors of fireworks. You should go read both of those, they’re excellent.

I’m a little late to this particular party, but I’m going to sort of split the difference between these two, and talk about the meaning of “color” a little. That is, when we talk about the color of something that emits light, what exactly do we mean? It turns out that if you want another person to see a particular color of light, science tells us there are three ways to make that happen , and two of the three are very directly quantum-mechanical.

Emission Lines

A young Niels Bohr (photo from Library of Congress) and a cartoon version of his atomic model, in which atoms emit light as the electrons move from one allowed orbit to another.

A young Niels Bohr (photo from Library of Congress) and a cartoon version of his atomic model, in which atoms emit light as the electrons move from one allowed orbit to another.

The most versatile source of colored light is what Hilary Brueck describes in talking about fireworks, namely the characteristic colors of light emitted by particular chemical elements. Each element in the periodic table has a unique set of wavelengths it will absorb and emit, so finding the color you want is just a matter of choosing the correct element that emits at that wavelength.

The basic phenomenon of “spectral lines” (as these discrete wavelengths are called, because in a traditional spectrometer light passes through a narrow slit before being dispersed by a prism or grating, and the light from a particular atom shows up as colored stripes, images of the slit) was discovered in the 1850′s. It was quickly embraced as a tool for identifying particular elements– the first evidence of the element helium was spotted in 1868, as a line in the spectrum of the Sun that didn’t match any known element (though helium gas wasn’t isolated on Earth until 1895), and through the late 1800′s new chemical elements were regularly identified by the light they gave off.

The reason for this remained obscure, though, until 1913, when Niels Bohr, a Danish theoretical physicist, proposed a revolutionary model of hydrogen. Bohr was working with Ernest Rutherford in Manchester, whose had introduced the idea of the atom as a miniature Solar System, with negatively charged electrons orbiting a positive nucleus containing most of the mass of the atom. This explained observations made by Rutherford and his students, but was impossible given the physics known at the time– according to classical physics, an orbiting electron should spew x-rays in all directions, and rapidly lose energy, spiraling into the nucleus.

Bohr made the radical suggestion that electrons orbiting atoms have certain special orbits in which, for some reason, they don’t emit any radiation at all, but go round and round very happily, basically forever. In this model, atoms absorb and emit only when electrons move between orbits, and the wavelength is determined by the energy difference between the two allowed orbits. Some simple assumptions let you calculate the exact pattern of wavelengths emitted by hydrogen, and these match observations almost perfectly.

Bohr’s model kicked the development of quantum physics into high gear. It wasn’t perfect– the base model didn’t work for any atom more complicated than hydrogen– but this kicked off almost a decade of what’s now known as “the old quantum theory,” adding various tweaks to Bohr’s basic idea to explain the spectrum of other elements. This got pretty baroque before the whole thing was scrapped in favor of the modern version of quantum mechanics, in the mid-to-late 1920′s, but the central concept remains: electrons inside atoms have a set of discrete states in which they can happily exist without emitting anything, and they absorb and emit light only when they move between these states.

The characteristic colors of fireworks, then, are a direct consequence of quantum physics.  When you set a sample of some element on fire, electrons in the atoms are excited to very high states, sometimes stripped off the atom entirely, and over a short time, they fall back to the lowest energy state available. Along the way, they emit basically all of the wavelengths possible for that particular element (some more strongly than others), leading to the characteristic colors we see.

(While I’m primarily talking about ways to make things emit light of particular colors, this is also the basic mechanism for coloring light by transmission or reflection. The colors we see for opaque objects come about because the molecules used to color them absorb particular colors more efficiently. What they don’t absorb bounces off, and reaches our eveys as light of a particular color.)

Blackbody Radiation

Max Planck in 1901 (photo from Wikimedia) next to n incandescent bulb and its spectrum. Image by Chad Orzel.

Max Planck in 1901 (photo from Wikimedia) next to an incandescent bulb and its spectrum. Image by Chad Orzel.

The other quantum-mechanical way to make color is even simpler: just get an object hot. Rhett Allain talks about this directly in discussing incandescent light bulbs, and Brueck alludes to it when she notes that higher temperatures in fireworks lead to paler colors.

The physics here is “black-body radiation,” which I’ve talked about before when I discussed light bulbs. It’s a simple, universal relationship explained mathematically by Max Planck (the slightly crazed looking fellow in the photo above): no matter what an object is made of, if you get it hot (but not so hot that it loses structural integrity), it will emit a broad spectrum of light whose peak wavelength depends only on the temperature.

Planck’s explanation of black-body radiation was the first introduction of quantum ideas– to explain the mathematical formula describing the spectrum, he was forced to pretend that the amount of light emitted at a particular wavelength could only come in multiples of a characteristic energy that depends on the wavelength. Planck himself was never that happy with this idea, but it set the stage for Einstein’s revolutionary contribution to quantum physics, and that, in turn, is crucial for Bohr’s atomic model.

As a way of making colored light, though, black-body radiation is pretty limited.  You get a particular color for a particular temperature, and that’s it– hot objects glow red, shading to orange, then yellow, then white as the temperature increases. This effect allows us to identify the temperatures of distant stars, which in turn provides clues to the physics at work to make them shine, so it’s a tremendously useful tool for physics. If your goal is to make a light that appears, say, green, though, you’re out of luck, because of the third factor involved in producing color.

Human Vision

The narrow spectrum of a violet laser, and the broad spectrum of the light a computer monitor uses to match the apparent color. (Image by Chad Orzel)

The narrow spectrum of a violet laser, and the broad spectrum of the light a computer monitor uses to match the apparent color. (Image by Chad Orzel)

The peak wavelength emitted by the Sun is around 500nm, and in fact is pretty close to what most people would call green– all the green shades of grass and leaves and so on ultimately comes from reflected sunlight, after all. But the sun doesn’t appear green to our eyes, because of all the other wavelengths that come along with it. And what we perceive as color is as much a product of biology as physics.

The best demonstration of this is the color “purple,” which any preschooler can tell you is made by adding red and blue. That color addition has no basis in physics, though, but is the result of a quirk of human biology. Our eyes construct what we perceive as color from the response of three types of cells in our retina, each sensitive to light of a particular range of colors. One is most sensitive to blue-ish light (short wavelength), one is most sensitive to red light (long wavelength), and the third to a sort of yellow-green. Based on how strongly each of these cells responds to incoming light, our brains construct our perception of color.

This means that we can trick a human brain into seeing a color that isn’t really there , just by getting the right mix of red, green, and blue light. This is illustrated in the image above, which plots the spectrum of a laser with a peak wavelength of 405 nanometers against the spectrum of light from a computer monitor set to something that closely matches the laser color, at least according to my eye. The monitor output is a broad mush of blue, green, and red, with basically no light at the actual wavelength of the laser, but thanks to the human brain, the perceived color is very similar.

(That image is from this video that I made as an entry for the “Flame Challege” contest a couple of years ago, which goes into more detail about all this.)

So, those are the three ways you can make a particular color: choose an element that emits the particular color you want; heat an object to the appropriate temperature; or trick the human brain into seeing a color that isn’t there thanks to the quirks of human vision.

Chad Orzel is a physics professor, pop-science author, and blogger. His latest book is Eureka: Discovering Your Inner Scientist (Basic Books, 2014).

July 7, 2015
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Hurley: Leave Hanley Ramirez Alone!

BOSTON (CBS) — It’s long been believed that Boston is a difficult place to play. Whether it’s been due to the high demands from fans, the watchful eyes in the press box, the expectations to live up to big-money contracts or for many years the weight of “The Curse” hanging overhead, a number of players throughout history have wilted while wearing a Red Sox uniform.

And to be sure, Hanley Ramirez is not one of them.

Yet, given the way he’s been discussed lately, you’d think the guy was a bum.

A June 30 Nick Cafardo mailbag in The Boston Globe ran the headline “Why don’t the Red Sox trade Hanley Ramirez?” The reason, Cafardo answered, is that no other teams would be willing to trade for him. The Globe’s Peter Abraham printed an exchange between Ramirez and reporters, one that left itself open to the interpretation that Ramirez might have been begging out of the lineup, despite being cleared medically. Felger and Mazz said on Sports Hub airwaves that the Red Sox are a better team without Ramirez. Michael Felger, Bob Ryan and Dan Shaughnessy dedicated an entire TV segment to that very discussion.

Every talk radio show in town — and even the NESN postgame show — was quick to criticize Ramirez for getting hit with a Xander Bogaerts line drive recently, as if it’s a piece of cake to avoid a ball traveling 100 mph while you’re running full speed in one direction.

Stop it.

We’ll get to the criticisms in a moment, but here are the facts: 18 home runs, 43 RBIs, .827 OPS.

In those categories, here are where Ramirez ranks on the team: first, first, first.

And here’s one more fact: Hanley Ramirez has been exactly what everyone should have expected — for better and for worse.

Hanley Ramirez is without a doubt someone who carries himself like a big-ego superstar, or a diva, or whatever word you’d prefer to use. But this isn’t a break in character. Not in the least.

In Florida, he was so headstrong that after getting pulled from a game for a lack of hustle in 2010, he publicly bashed manager Fredi Gonzalez, saying, “He never played in the big leagues.”  This was a couple of months after Marlins owner Jeffery Loria bought a nice diamond-studded pendant for Ramirez, so it’s not hard to see how the player came to feel so entitled.

In Los Angeles, Ramirez caused Don Mattingly to age at warp speed — largely because Ramirez refused to play through a number of minor injuries. Sound familiar?

This is the player the Red Sox targeted in free agency. This is the player they ultimately chose to give between $88 million and $107 million.

He’s come exactly as advertised.

And signing Ramirez is fine. The Red Sox needed right-handed power. He’s producing at the plate. (The Red Sox also targeted Rick Porcello and then decided to throw $82.5 million at him. That decision seems slightly more problematic, don’t you think?)

Of course, Hanley is a worse left fielder than anybody could have imagined, but aren’t the Red Sox on the hook for assuming Ramirez could play a position he’s never played? Surely, Hanley could be working harder to improve out there, but if the Red Sox expected a determined focus out of him to improve defensively, then that’s on them.

On the basepaths, Ramirez actually does hustle — at least, he hustles more than David Ortiz ever has, and nobody’s ever taken issue with Ortiz’s commitment to the game.

In general, Ramirez is aloof. He forgets how many outs there are and he doesn’t keep track of his own balls and strikes.

But he also launches one-handed, game-winning moon shots over the Green Monster.

Through three months in Boston, Hanley Ramirez has been — perfectly — Hanley Ramirez.

There are a number of reasons why the Red Sox can win eight of 12 yet still sit six games under .500 and six games out of first place. Ramirez’s annoying, occasionally obnoxious idiosyncrasies are far, far down that list.

Is it embarrassing to make excuses for an adult man who has the tendency to act like a child? Of course. We learned by the end of Manny Ramirez’s eight-year career in Boston that if you defend such a player, you’ll often end up with egg on your face.

But you don’t have to excuse the behavior to accept it as reality.

Hanley Ramirez is going to be Hanley Ramirez. Always.

If you expect him at 31 years old to suddenly become a different person, then that’s your problem, not his.

Read more from Michael Hurley by clicking here. You can email him or find him on Twitter @michaelFhurley.

July 7, 2015
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Pre-Market News Alert on: General Mills, (NYSE:GIS), First Horizon National …

On Monday, General Mills, Inc. (NYSE:GIS)’s shares declined -0.82% to $56.58.

General Mills (GIS) said that the board of directors declared a quarterly dividend at the prevailing rate of 44 cents per share, payable August 3, 2015, to shareholders of record July 10, 2015. The General Mills quarterly dividend rate was most recently raised 7 percent effective with the May 1, 2015 payment. General Mills and its predecessor firm have paid dividends without interruption or reduction for 116 years.

General Mills, Inc. manufactures and markets branded consumer foods in the United States and internationally. It also supplies branded and unbranded food products to the foodservice and commercial baking industries. The company operates in three segments: U.S. Retail, International, and Convenience Stores and Foodservice. Its products comprise ready-to-eat cereals; convenient meals, counting meal kits, ethnic meals, pizza, frozen breakfast, and frozen entrees; snacks comprising grain, fruit, and savory snacks, in addition to nutrition bars and frozen hot snacks; refrigerated yogurt products; ice creams; baking mixes and ingredients; refrigerated and frozen dough products; and frozen and shelf-stable vegetable products. In addition, the company’s products comprise organic products, such as granola bars, cereals, and soups.

First Horizon National Corp (NYSE:FHN)’s shares gained 0.38% to $15.65.

First Horizon National Corp (FHN) a Memphis, TN-based financial services company on Jun 22, 2015. The company has attractive growth prospects given its various restructuring initiatives in addition to an extended focus on cost control.

Since 2008, First Horizon has been effectively divesting its mortgage and legacy national lending portfolios, and intends to continue with the planned wind down. Such measures will provide the company with additional resources, giving it an opportunity to deploy excess capital through dividend increments and share buybacks.

Further, First Horizon has been cautiously controlling expenses through process improvement, branch network optimization and other efficiencies together with lowering its corporate real estate footprint. It is also attempting to curtail its annual expenses by another $20–$50 million, going forward. Notably, non-interest expenses have declined at a 3-year CAGR of 22% (2012–2015). This is likely to enhance the company’s bottom-line expansion.

First Horizon National Corporation operates as the bank holding company for First Tennessee Bank National Association that provides various financial services in the United States and internationally. The company offers general banking services for consumers, businesses, financial institutions, and governments. It also provides investments, financial planning, trust, asset administration, credit card, and cash administration services.

At the end of Monday’s trade, Carnival Corp (NYSE:CCL)‘s shares dipped -1.00% to $49.36.

Holland America Line has broken ground on a new “Base Camp” complex at the company’s McKinley Chalet Resort near the entrance to Alaska’s Denali National Park. Predictable to be complete for the 2016 Alaska cruise season, Base Camp is part of Holland America Line’s ongoing enhancement program at the property that also comprises room updates, upgrades to soft goods and hotel decor and additional modifications.

The McKinley Chalet Resort provides accommodations for guests on Holland America Line’s Land+Sea Journeys that combine an Alaska cruise with an overland tour to Denali National Park and beyond. Base Camp will be centrally located between the main part of the property, containing the reception hall, dining facilities and guest rooms, and the riverfront guest rooms that provide stunning views of the Nenana River.

Carnival Corporation operates as a cruise company worldwide. It provides vacations to various cruise destinations. The company offers cruise services under the Carnival Cruise Lines, Holland America Line, Princess Cruises, and Seabourn brand names in North America; and AIDA Cruises, Costa Cruises, Cunard, and PO Cruises names in Europe, Australia, and Asia. It operates 100 cruise ships. It also owns and operates 12 hotels or lodges, and about 300 motor coaches and 20 glass-domed railcars. The company sells its cruise services through retail, online and home-based agents, wholesalers, general sales agents, and tour operators. Carnival Corporation was incorporated in 1972 and is headquartered in Miami, Florida.

Intrexon Corp (NYSE:XON), ended its Monday’s trading session with 3.51% gain, and closed at $47.54.

Intrexon Corporation (XON) declared that it has reached a partnership with an investment fund sponsored by Harvest Capital Strategies, LLC. The fund is believed to be the world’s first that is dedicated to the inventions and discoveries of a single company.

Intrexon has agreed to provide the fund a noteworthy number of investment proposals from across five sectors – Health, Energy, Food, Environment and Consumer – that are suitable for pursuit by a startup, counting several in 2015. With respect to such proposals, Intrexon will provide the fund with exclusive rights of first-look and first negotiation. Intrexon presently sees the potential to form up to ten new companies per year, each of which will have access to Intrexon’s proprietary technology platform through an Exclusive Channel Collaboration. Although the partnership with the fund will be complimentary to programs already underway at Intrexon, nothing in the arrangement will limit the Company’s ability to execute other collaborations and joint ventures.

Intrexon Corporation, a biotechnology company, operates in the synthetic biology field in the United States. The company, through a suite of proprietary and complementary technologies, designs, builds, and regulates gene programs, which are DNA sequences that comprise of key genetic components. Its technologies comprise UltraVector gene design and fabrication platform, and its associated library of modular DNA components; cell systems informatics; RheoSwitch inducible gene switch; AttSite Recombinases; protein engineering; mAbLogix; and laser-enabled analysis and processing. Intrexon Corporation has partnership agreements with ZIOPHARM Oncology, Inc.; Synthetic Biologics, Inc.; Oragenics, Inc.; Fibrocell Science, Inc.; Genopaver, LLC; AquaBounty Technologies, Inc.; S I Ophthalmic, LLC; Biological Popular Culture, Inc.; OvaXon, LLC; Intrexon Energy Partners, LLC; and Persea Bio, LLC; and planned partnershipand licensing agreement with Merck Serono S.A. The company was formerly known as Genomatix Ltd. and changed its name to Intrexon Corporation in 2005. Intrexon Corporation was founded in 1998 and is based in Germantown, Maryland.

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July 7, 2015
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Conservation laws, radiative decay rates, and excited state localization in …

Octahedral model

Before considering the full pseudo-angular momentum model, H, it is important to understand the symmetries of Ho. (i) LL does not couple to any of the other variables. Therefore,

and

are good quantum numbers. (ii) We can define a ‘total’ angular momentum, I = LH + S, where S = SH + SL. I2 and Iz commute with Ho therefore I and Iz are also good quantum numbers.

We plot the energies of the exact solutions of Ho in Fig. 2 (Table 2 gives the basis used for all calculations in the paper). For simplicity Fig. 2 shows only the solutions with

—because LL is decoupled from the other angular momenta it can be immediately seen that the other solutions simply triple the degeneracies of all states. Note that, firstly, the spectrum of Ho is not very similar to those of the pseudo-octahedral complexes we are seeking to model. However, this model is an important stepping stone to understanding the full Hamiltonian. Secondly, the eigenstates can be classified by their total angular momentum quantum number, I, and, as Ho is SU(2) symmetric, have the expected 2I + 1 degeneracy. Thirdly, all of the singlets have I = 1; as LH = 1 and, by definition, singlets have S = 0. This means that, regardless of how strong the SOC is, the singlets can only mix with the I = 1 triplets. Therefore radiative decay from the I = 0 and I = 2 triplets is forbidden by the conservation of I.


Figure 2: Energy eigenvalues of Ho for states with LZ=0.

At λ = 0 the singlets have E = 3J/4 and the triplets have E = −J/4. For λ  0 the labels “singlet” and “triplet” are no longer strictly defined (in their usual sense) nevertheless the relatively small energy shifts suggest that these labels retain some meaning, this claim is supported by directly examining the character of the eigenstates. It is interesting to note that, already in the octahedral problem, the lowest energy (non-degenerate) state has no singlet contribution to its wavefunction for any value of λ, thus radiative transitions from this state are forbidden.

  • Full size image (181 KB)

Trigonal model

In Fig. 3 we plot the spectrum of the trigonal model with no Jahn-Teller distortion, Ho + Ht. Again, for simplicity, we only show the solutions with

. In this case each state has partners with

that have energies that are higher by Γ and display twice the degeneracy of the

state. The trigonal terms break the SU(2) symmetry of the octahedral model and therefore lift the three- and five-fold degeneracies. The calculated spectra are now like those calculated from first-principles for relevant complexes. For example, if trigonal symmetry is enforced for, e.g., [Os(bpy)3]2+, Ir(ppy)3, Ir(ptz)3 relativistic TDDFT calculations predict that SOC splits T1 into a non-degenerate state (I) and, at slightly higher energies, a pair of degenerate states (II and III)8, 9, 11.


Figure 3: Solution of the pseudo-angular momentum model of a trigonal complex.

a) spectra for λ = J/5 and varying Δ/J; b) spectra for Δ = J/2 and varying λ/J. The quantum numbers of the states are also indicated. In both panels the states with quantum numbers labelled as

are two-fold degenerate. The eigenstates with Lz = ±1 (not shown for clarity) have the same properties except that their energies are increased by Γ and all of the degeneracies are doubled corresponding to the two values of Lz = ±1.

  • Full size image (334 KB)

We saw above that in the octahedral model radiative decay from the lowest energy excited state (I→0) is forbidden by the conservation of I. Because Ht breaks the SU(2) symmetry of the octahedral model I2 no longer commutes with H, nevertheless Iz and

remains a good quantum numbers for the trigonal model. Furthermore, the Hamiltonian is time reversal symmetric, therefore the parity of an eigenstate under time reversal,

, is also a good quantum number. Note however, that Iz does not commute with time reversal so it is not, in general, possible to form states that are simultaneously eigenstates of both. However, one may define states that are simultaneous eigenstates of the

and

. Therefore, we take these as our quantum numbers, cf. Table 2.

For all parameters studied substate I is composed of the basis state |T1〉 admixed with

and has quantum numbers

,

whereas states II and III are a degenerate pair with

,

,

, cf. Fig. 3, whose largest contributions come from |Tx〉 and |Ty〉. The singlet states with the same quantum numbers contribute to substates II and III, but all of the singlets are forbidden from mixing with substate I by the combination of time reversal symmetry and the conservation of Iz. Hence, the I→0 transition remains forbidden in the trigonal model. Both experiments1, 19 and relativistic TDDFT calculations8, 9, 10, 11 find that the radiative rates for the transitions II→0 and III→0 are more than an order of magnitude faster than that for I→0, cf. Table 2. A small non-zero decay rate for I→0 may arise from either Herzberg-Teller coupling1, 19 or mixing of state I with higher energy singlet states, which are not included in the pseudo-angular momentum model8, 9, 10, 11.

Full model

Finally, we turn to the full pseudo-angular momentum model, H [Eq. (9)]. Iz does not commute with HJT. However,

, where the ladder operators are given by

, therefore Iz is conserved modulo two. Thus, L z is conserved even for a trigonal system that has undergone a Jahn-Teller distortion, cf. Table 2. Similarly

is conserved modulo two, which gives rise to the quantum number

.

We plot the spectrum of Lz = 1 states in Fig. 4a. In Fig 4b, we plot the same results, but only show the three lowest energy substates, I-III, which are of primary technological interest. One sees that the although states II and III are degenerate at δ = 0, a Jahn-Teller distortion rapidly lifts this degeneracy and for reasonable values of δ one finds that there is a much smaller energy gap between substates I and II than between II and III. This is what is observed experimentally1, 19, 20 in a huge range of complexes (Table 1). We will see below that this splitting is the signature of the localization of the excitation to a single ligand.


Figure 4: Solution of the pseudo-angular momentum model of a complex with broken trigonal symmetry – due either to chemical modification or excited state localization.

Panel (a) shows the full spectrum for states with Lz = 1. Panel (b) shows only the T1 substates, which are our primary concern. Here we take Δ = J/2 and λ = J/5.

  • Full size image (292 KB)

Note, in particular, that substate I remains an admixture of |T1〉 with

and

and has quantum numbers

. As none of the singlet states have these quantum numbers, cf. Table 2, this state is forbidden from mixing with any of the singlet states in the model by conservation of

,

and

. Therefore substate I remains a pure triplet and is forbidden from decaying radiatively, irrespective of the strength of the SOC.

The radiative rate of the mth eigenstates of the full Hamiltonian, |ψm〉, is given by

where Em is the excitation energy of the mth state, and α is the fine structure constant. The |Sn〉 are only eigenstates for the octahedral model with λ = 0; therefore symmetry requires that 〈S0|μβ|Sn〉 is independent of n. Note that, notwithstanding this observation, in the full model the states one would usual think of as “singlets”, i.e., the three states with the largest contribution from the |Sn〉, all have different radiative rates because the octahedral symmetry is broken and the “singlets” have different contributions from the relevant |Sn〉. Furthermore we assume that the zero field splitting is small compared to the S0 → T1 excitation energy, i.e., that EI ⋍ EII ⋍ EIII It is also convenient to define

this corresponds to the radiative decay rate for a pure singlet with an excitation energy equal to that of the T1 manifold.

We plot the radiative decay rate in Fig. 5. State I is dark—as expected from the conservation laws derived above. Furthermore, once the Jahn-Teller distortion becomes significant one finds that the radiative decay from state II is significantly slower than the radiative decay from state III. This is in precisely what is observed in experiments1, 19, 20 on pseudo-octahedral d6 complexes (cf. Table 1).


Figure 5: The radiative decay rates of the three substates of T1.

The conservation of

,

, and

leads to the absence of radiative decay for state I. It can be seen that once the Jahn-Teller distortion becomes significant the radiative decay rate from state II is significantly smaller than that from state III, in good agreement with experiment (cf. Table 1). Here, as above, we take Δ = J/2 and λ = J/5.

  • Full size image (138 KB)

It is straightforward to understand both the changes in energy and the radiative rates of states II and III. For δ  0 (δ  0 simple reverses these effects) the trigonal perturbation lowers the energy of (stabilises) states that are antibonding between the

orbitals, e.g., |Sx〉 and |Tx〉, and raises the energy of (destabilises) those that are bonding between the

orbitals, e.g., |Sy〉 and |Ty〉. It is clear from Table 2 that whereas |Sx〉 and |Ty〉 are even under time reversal |Tx〉 and |Sy〉 are odd. Thus, SOC mixes |Sx〉 with |Ty〉 and |Sy〉 with |Tx〉. Hence the trigonal distortion increases the energy difference between the triplet and singlet basis states that contribute to state II (i.e., |Sx〉 and |Ty〉 for δ  0); whereas trigonal symmetry reduces the energy difference between the triplet and singlet basis states that contribute to state III (|Sy〉 and |Tx〉 for δ  0). Thus the symmetry of the model dictates that

, as is observed experimentally1, 19, 20, see Table 1.

Finally, we turn to the question of localization in the excited state. To measure this we define

where

annihilates (creates) a hole with spin σ in π orbital of the mth ligand. Thus Ξψ measures the probability of the hole being found on ligand 0 when the system is in state ψ—with Ξψ  0 indicating localisation onto ligand 0 and Ξψ  0 signifying a reduced probability of the hole being found on ligand 0. We plot Ξψ for the three substates of T1 in Fig 6. The lowest energy excitation, I, is completley delocalized for δ = 0 but rapidly localizes for δ  0. It is interesting to note that both ΞII and ΞIII are non-zero for δ = 0. However, for δ = 0 states II and III are degenerate and ΞII = −ΞIII, consistent with trigonal symmetry. Nevertheless, for δ  0, one observes a rapid increase in ΞII whereas ΞIII grows only rather slowly.


Figure 6

The degree of localization in the three substates of T1, ν ∈ {I,II,III}, where

. Here, as above, we take Δ = J/2 and λ = J/5.

  • Full size image (118 KB)

It is therefore clear that the pseudo-angular momentum model predicts significant localization of states I and II for values of δ compatible with the observed experimental results that

and EI,II  EII,III, cf. Table 1. We therefore conclude that all of the complexes in Table 1 show significant localization in their excited states.

July 7, 2015
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The Latest: Pope wraps up visit in Guayaquil, flies to Quito

Here are the latest developments from Pope Francis’ trip to South America:

5:20 p.m.

The pope has wrapped up a seven-hour stay in Ecuador’s biggest city and is flying back to the capital of Quito.

During the day, Pope Francis celebrated an outdoor Mass for hundreds of thousands of people gathered under a broiling sun at Samanes Park on the northern edge of the port city of Guayaquil.

He then had a private lunch with fellow Jesuits, before heading to the airport and his plane back to Quito.

5:05 p.m.

Pope Francis had a chance to sample seafood from the Ecuadorean coast while meeting with fellow Jesuit priests in the port city of Guayaquil.

The entrees were shrimp ceviche and a chicken broth. Then the main course was grilled sea bass. Desert was tropical fruit and sweets made by women who work in a Jesuit school in Portoviejo, about 85 miles (136 kilometers) north of Guayaquil.

The Rev. Pedro Barriga, the 89-year-old leader of the Jesuit school in Guayaquil, says the meal last nearly an hour. He says the meeting was very informal, and the pope went around and shook everybody’s hand.

Were the dishes tasty?

“Don’t ask me about the food,” Barriga said with a laugh. “I have poor taste. I eat everything they put in front of me.”

4:30 p.m.

Before Monday, it had been 30 years since the Rev. Francisco Cortes last saw Pope Francis, who then was simply the Rev. Jorge Mario Bergoglio and was in charge of the Jesuit order in Argentina.

The now nearly 91-year-old Cortes must have made a strong impression with his work at the Colegio Javier parochial school mentoring young men sent to him by the future pontiff. His meeting with Francis on Monday was the only private one-on-one session that the pope scheduled for his visit to Ecuador.

After Francis arrived following a huge outdoor Mass in Guayaquil, Cortes gave a bouquet to the pontiff and they embraced.

Cortes told The Associated Press earlier that he was perplexed by the pope’s invitation.

In his words, “I don’t know why he set the meeting. We haven’t even corresponded. I’m really just a Mr. Nobody.”

2:45 p.m.

Pope Francis has arrived at a Jesuit-run secondary school in Guayaquil for lunch with a handful of fellow Jesuits.

Two youngsters presented Francis with flowers and other gifts as he arrived at the Colegio Javier. In exchange, they received a papal hug.

Francis also could be seen embracing an elderly man. While at the school, the pope is scheduled to meet with the Rev. Francisco Cortes, the 91-year-old headmaster known affectionately as “Padre Paquito.”

When Francis was the Rev. Jorge Mario Bergoglio in his native Argentina, he used to send his seminarians on study trips to the Javier school in Guayaquil, entrusting them to Cortes.

Cortes has said the last time he spoke to Bergoglio was some 30 years ago and he couldn’t believe the pope remembered him.

1:30 p.m.

Flags of more than half a dozen countries can be seen waving in the air at a Mass that Pope Francis is celebrating in Guayaquil, a humid port city that is Ecuador’s largest.

The variety of flags include: Ecuador, Mexico, Peru, the United States, Argentina, Colombia, Brazil, Chile and Puerto Rico.

“I didn’t want to miss the opportunity to see Francis,” said Norma Peralta, from neighboring Peru. “It took me about 10 hours driving to get here. It’s cheaper than going to the Vatican.”

1:05 p.m.

Pope Francis is focusing his homily on the family while celebrating Mass at a large park in Ecuador’s coastal city of Guayaquil.

Francis gave the example of a mother and her children, saying she loves all of them equally.

“The family is also a small church, a domestic church,” said Francis. “With life, it channels tenderness and divine mercy.”

Hundreds of thousands listened to the pope at Semanes Park while standing in the hot sun and using handkerchiefs to wipe sweat from their brows.

12:06 p.m.

Hundreds of thousands of faithful cheered Pope Francis as he arrived at the Semanes Park in Guayaquil. The pope planned to celebrate Mass at the park in the Ecuadorean coastal city, the country’s largest with 2.35 million residents.

Riding in the popemobile, Francis waved to the crowds. People waved handkerchiefs and Vatican flags.

The port city is known for its heat and humidity, at noon was already 86 degree Fahrenheit (30 degrees Celsius).

11:05 a.m.

Pope Francis has arrived at the Divine Mercy shrine in the Ecuadorean coastal city of Guayaquil. Upon arrival to the shrine, the outstretched hand of a young child nearly poked Francis in the eye. The pope smiled as he continued walking.

Francis then spent a minute praying at the shrine beneath a large painting of Jesus. The pope told the crowd he would pray for them.

“And I won’t charge you a thing,” he joked. “All I ask is that you pray for me. Will you promise me that?”

After visiting the shrine, the pope plans to celebrate Mass at a park with more than 1 million people.

10:43 a.m.

A self-proclaimed “Mr. Nobody” soon will be sharing the spotlight with one of the world’s most famous people.

It’s been 30 years since the Rev. Francisco Cortes last spoke with Pope Francis, who at that time was the Rev. Jorge Mario Bergoglio.

Cortes, known as Padre Paquito, must have made quite an impression on Bergoglio, who in Argentina was in charge of the Jesuit order that the men share.

Cortes, who is 91 years old and a Spaniard by birth, was to spend five minutes with the pope on Monday. They will meet in a small room adorned by flowers and religious paintings after Francis celebrates an outdoor Mass in the Ecuadorean coastal city of Guayaquil.

“I don’t know why he set the meeting. We haven’t even corresponded,” Cortes told The Associated Press in an interview. “I’m really just a Mr. Nobody.”

10:03 a.m.

A handful of altar boys took selfie photos with Pope Francis upon his arrival in Guayaquil, a port city in Ecuador where the pope plans to celebrate Mass with up to 1 million people. The altar boys were waiting on the tarmac and approached the pontiff when he descended from his plane.

Francis also was met by Mayor Jaime Nebot, who gave him the keys to the city, which were gold and silver, encrusted with pearls.

9:56 a.m.

Pope Francis has landed in Guayaquil, an Ecuadorean port city where he plans to celebrate Mass in a park. More than 1 million people are expected to attend Mass at the Samanes Park in northern Guayaquil.

While in the city, Francis also plans to meet with members of his Jesuit order.

9:15 a.m.

If nature calls while Pope Francis is celebrating Mass in Ecuador’s port city of Guayaquil, a special bathroom is set up for him.

Sitting behind the pavilion in the Samanes Park, authorities built a spacious bathroom that includes a large toilet, a shower, a large mirror, an Asian-style rug and a painting of Jesus.

Teresa Arboleda, a popular television personality in Ecuador, toured the bathroom and described it to viewers. She says the bathroom has white walls and light that shines in from above giving it a bright feel.

More than 1 million people are expected to attend Mass at the park.

8:05 a.m.

Hours before Pope Francis arrives in Ecuador’s port city of Guayaquil, thousands are already waiting in the Samanes Park where the pope is expected to celebrate Mass with up to 1 million people.

Guillermina Aveiga Davila, a 90-year-old retired accountant, says she arrived in the middle of the night. She traveled from Chone, about 104 miles (167 kilometers) north of Guayaquil.

“This is the first time I’ll be able to see a pope,” said Davila, accompanied be five family members.

Vicente Huilcatoma Montes, a 47-year-old school bus driver, says he arrived at 5 p.m. on Sunday to make sure he found a good spot close to the front. He says he walked 25 miles (40 kilometers) with a procession from the southern part of Guayaquil to the park, which is in the far northern part of the city.

“I’m tired, hungry and I haven’t slept but I feel such emotion and joy in my heart,” he said.

July 7, 2015
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Neandertals create oldest jewelry in Europe

Neandertals fashioned the oldest known piece of jewelry in Europe, a new study suggests. The 130,000-year-old necklace or bracelet had featured eight claws from white-tailed eagles.

This personal ornament was created roughly 60,000 years before modern humans — Homo sapiens — reached Europe. That’s the conclusion of paleontologist Davorka Radovčić (Raah-dah-VEECH-eech) and her team. Radovčić works at the Croatian Natural History Museum in Zagreb. This jewelry was found in a rock shelter in Croatia, part of central Europe. Neandertal remains also showed up at this site, called Krapina (Krah-PEE-nah).

The claws showed marks made by some tool. There were also polished spots that would have come from wear. This suggests the claws had been deliberately removed from eagles, strung together and worn, the researchers say.

They described their findings March 11 in the journal PLOS ONE

Some researchers had argued that Neandertals didn’t make jewelry. Some had doubted that these hominids even engaged in such symbolic practices until after they witnessed them in our species: Homo sapiens. But the age of the claws indicates that Neandertals were already accessorizing their bodies long before encountering modern humans.

White-tailed eagles are a fierce and majestic predator. Given how hard it would have been to get their talons, a piece of eagle-claw jewelry must have had great significance for Neandertals, the scientists argue.

“To discover evidence of what’s widely regarded as typical modern behavior [body ornamentation with jewelry] at such an ancient Neandertal site is stunning,” says David Frayer. A paleoanthropologist, he coauthored the new study. Frayer works at the University of Kansas in Lawrence.

Dating the ancient jewelry

Radovčić noticed incisions on the set of eagle talons. These scored marks looked like they had been deliberately made by a sharp tool. That was back in 2013. At the time, she had been surveying fossils and stone tools recovered more than a century ago at Krapina.

Her team estimated the age of Neandertal teeth at the site. To do this, they used a technique known as radioactive dating. Natural radioactive trace elements in the teeth change (decay from one isotope into another) at a fixed rate. That dating showed that the Krapina Neandertals lived roughly 130,000 years ago.

Under the microscope, marks on the talons appear to be incisions made while someone removed those claws from the birds’ feet. The jewelry maker likely wrapped string around the ends of the talons and over the tool marks to make a wearable object, Radovčić’s team says. Incisions on strung claws developed polished edges. The most likely explanation, the researchers say, is that these shiny spots developed when the claws rubbed against the string. Eagle claws on the Krapina ornament would have come in contact with each other when the jewelry was worn. And there are signs of this on the talons’ sides, the researchers note. No string turned up.

Paleoanthropologist Bruce Hardy works at Kenyon College in Gambier, Ohio. In 2013, his team reported finding that Neandertals twisted fibers to make string at a cave in southeastern France. That string was nearly 90,000 years old. “Evidence for Neandertal symbolic behavior continues to mount,” Hardy says. “And the Krapina talons significantly push back the date of that behavior,” he adds.

Ogling eagle bits

This wasn’t the first sign of talon appreciation in Neandertals. Individual eagle talons, possibly used as pendants, showed up at a handful of later Neandertal sites. Some dated to 80,000 years ago, Frayer says. Still, that’s 50,000 years later than those found at the Krapina site.

The Krapina claws include three second talons from a bird’s right foot. That means that at least three birds would have been needed to make this ornament.

“The evidence points to a special relationship between Neandertals and birds of prey,” says Clive Finlayson. He’s an evolutionary ecologist at the Gibraltar Museum. He was not part of the new study. In a controversial earlier finding, Finlayson reported that Neandertals decorated themselves with bird feathers.

Neandertals likely caught white-tailed eagles, he says. Present-day white-tailed and golden eagles frequently feed on the carcasses of animals, he says. “White-tailed eagles look impressive and dangerous but they behave like vultures.” To catch them, Neandertals could have baited eagles with pieces of meat placed on covered traps. Or they could have thrown nets over the animals as they fed on strategically placed snacks.

Power Words

(for more about Power Words, click here)

behavior  The way a person or other organism acts towards others, or conducts itself.

carcass  The body of a dead animal.

evolutionary ecologist  Someone who studies the adaptive processes that have led to the diversity of ecosystems on Earth. These scientists can study many different subjects, including the microbiology and genetics of living organisms, how species that share the same community adapt to changing conditions over time, and the fossil record (to assess how various ancient communities of species are related to each other and to modern-day relatives).

fossil  Any preserved remains or traces of ancient life. There are many different types of fossils: The bones and other body parts of dinosaurs are called “body fossils.” Things like footprints are called “trace fossils.” Even specimens of dinosaur poop are fossils.

hominid   A primate from an animal family that includes humans and their fossil ancestors.

Homo  A genus of species that includes modern humans (Homo sapiens). All had large brains and used tools. This genus is believed to have first evolved in Africa and over time its members continued to evolve and radiate throughout the rest of the world.

incision     (v. to incise) A cut with some blade-like object or marking that has been cut into some material. Surgeons, for instance, use scalpels to make incisions through the skin and muscle to reach internal organs.

isotope   Different forms of an element that vary somewhat in weight (and potentially in lifetime). All have the same number of protons, but different numbers of neutrons in their nucleus. That’s why they differ in mass.

Neandertal  A hominid species (Homo neanderthalensis) that lived in Europe and parts of Asia from about 200,000 years ago to roughly 28,000 years ago.

paleoanthropology    The study of the culture of ancient people or human-like folk, based on the analysis of remnants, artifacts or markings created or used by these individuals. People who work in this field are known as paleoanthropologists.

paleontologist  A scientist who specializes in studying fossils, the remains of ancient organisms.

predator  (adjective: predatory) A creature that preys on other animals for most or all of its food.

prey  Animal species eaten by others.

radioactive  An adjective that describes unstable elements, such as certain forms (isotopes) of uranium and plutonium. Such elements are said to be unstable because their nucleus sheds energy that is carried away by photons and/or and often one or more subatomic particles. This emission of energy is by a process known as radioactive decay.

talon    The curved toenail-like claw on the foot of a bird, lizard or other predatory animal that uses these claws to snag prey and tear into its tissues.

trait   A characteristic feature of something.

July 7, 2015
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A round-up of Sunday editorials from Florida’s leading newspapers:

In Florida, when activists, donors, elected officials lobbyists, operatives, reporters, supporters, volunteers — and most important — voters talk about a story they read “in the blogs” they are likely talking about SaintPetersBlog, one of Florida’s most influential political websites with more than 25,000 unique visitors per day.

SaintPetersBlog is recognized by the Washington Post as one of the best blogs in the country and is edited and published by Extensive Enterprises Media. 

Executive Editor: Peter Schorsch. Contact Peter at Peter@Extensive-Enterprises.com or 727.642.3162.

Contributors and reporters: Phil Ammann, Mitch Perry, James Call, Janelle Irwin, Ryan Ray, Bruce Ritchie, Christine Sexton, and Florence Snyder.

Edited by Rich Bard and Bill Prescott.

July 6, 2015
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New Cold War with Russia? Learn the right lessons




A secret intelligence report about Moscow’s aggressive intentions predicts “an airborne invasion involving bombing and the dropping of paratroopers.” But the probable targets are listed not as Kiev, Tbilisi, Vilnius, or Tallinn but as “Nome, Fairbanks, Anchorage, and Seward.” Right: Alaska. The report, only recently declassified by the US government, dates to 1951. It describes a secret collaboration between the FBI and Air Force counterintelligence to prepare for a successful Soviet invasion of Alaska by training a cadre of nearly 100 “stay-behind-agents” — undercover backwoodsmen, bush pilots, anglers — to spy on the Red Army occupiers. “Survival caches” of supplies and radio gear were hidden in remote locations, ready for use. From 1951 to 1959, the stay-behind agents stood ready.

It never came to that, but the revelation of the program, dubbed Operation Washtub, provokes an eerie resonance today. Russia, having invaded Georgia and seized Crimea, is now flouting its border with Ukraine. Citizens of half a dozen European countries in Moscow’s “near abroad” find that fear of invasion no longer seems paranoid. For me, news of the declassification landed with a personal jolt, since it identified the Air Force intelligence officer in charge of Washtub as my father, then-Brigadier General Joseph Carroll. Good God, Dad, what were you thinking?

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But it’s not that hard to figure out. When Washtub began, Joseph Stalin was in power. That murderer of 20 million of his own countrymen had enslaved Eastern Europe, and had recently ended the American monopoly on the atomic bomb. With Communist China ascendant, Stalin was riding high. From Washington, it did not seem paranoid to imagine his move across the 50-mile wide Bering Strait.

In hindsight, though, the Cold War fears of Americans were indeed paranoid, generating catastrophic Red Scare overreactions at home, and hugely self-destructive adventures abroad, eventually including Vietnam.

But before condescending to America’s Cold War leaders who put in place the structures of opposition to the tyranny of the USSR, including for a time the now ludicrous and ludicrously named Operation Washtub, one would do well to recall that across the half-century of the Washington-Moscow standoff, those officials sustained a strategic system of containment and deterrence that, for all its dangers, evolved into detente, arms control, arms reduction, and trust. The tribunes of our garrison-nation never imagined that the Soviet empire was capable of being dismantled without war, yet it was. We thank our lucky stars that World War III was averted, but, given the slender thread on which the human future hung, we should thank the Cold Warriors, too. Such gratitude has come to define the heart of my memory of my father, who was one of them.

The point is that, across decades in which the East and West avoided mass war, the corruptions of Soviet Communism undid themselves, and the virtues of liberal democracy re-shaped the political conscience of much of the world — including of a surprisingly self-critical United States, which in that same era underwent its own civil rights and peace-movement revolutions. Ultimately, Americans found it possible to follow a Russian’s lead in ending the Cold War. Humane change, that is, was given space and time to remake societies on both sides of the divide.

But that peaceful denouement seems jeopardized now, as Vladimir Putin, shoring up his political standing at home, ignites a new nationalist aggressiveness abroad — not only threatening neighboring states and unsettling the post-Cold War order of Europe, but sowing seeds of mayhem to sprout in the Middle East, too. Putin is trouble.

Catastrophic Red Scare overreactions were generated.

What is America to do now? The answer is complex. The problems are larger than anything Washington caused, and larger than anything Washington, acting alone, can resolve. Measured American leadership is needed. Realistic assessments of danger are needed, too. In any resuscitated hostility with Moscow, the Cold War would inevitably become a point of reference. Yet it should not be the Red Scare paranoia that returns, but the steadily maintained structures of international cooperation, based on a final preference of dialogue over force, that once allowed the strengths of democratic value to prevail in far more dangerous circumstances.

Operation Washtub reads today like a Walter Matthau film script. But it was part of a campaign to buy time. And for all the excesses and abuses it unleashed, that campaign succeeded. There is something in America to trust.

James Carroll writes regularly for the Globe.