A Black Future

Tom Siegfried, the editor of Science News, seems to have decided to join with Michio Kaku in the science-fiction as science business. He marks the startup of collisions at the LHC with A Black Future, an article about how “the Large Hadron Collider might help humans explore the cosmos”. Here “exploring the cosmos” doesn’t mean understanding how the cosmos works, it means building an interstellar spaceship to travel across it.

The argument seems to be that the LHC will produce black holes, and a recent paper by Crane and Westmoreland suggests that black holes can be used to power a space-ship. Siegfried somehow manages to drag Steven Weinberg and supersymmetry into this, with a claim I don’t understand that the Crane-Westmoreland idea “may be realistic only if cosmic physics incorporates a mathematical framework known as supersymmetry.”

Posted in This Week's Hype | 19 Comments

50 Years of Nobel Memories in High Energy Physics

Over the past two days, CERN has been hosting a program consisting mostly of talks by Nobel prize winners in high energy physics, under the title 50 Years of Nobel Memories in High Energy Physics. It has been a while since anything Nobel Prize worthy has been discovered in HEP, so the speakers of necessity are all getting on a bit in years. The talks pretty much all seem worth paying attention to. Many of them are now on-line, and of the few I’ve had a chance to look at, the comments by Burt Richter about the ILC/CLIC issue were notable, as well as Veltman’s explanation of the possible significance of not finding a Higgs.

I started watching the webcast towards the end of David Gross’s talk, in time to hear him give his usual praiseworthy defense of physics against anthropic pseudo-science. Weinberg’s talk by video-conference was unfortunately cut short, since he thought it would be an hour long, but it was just scheduled for half an hour.

CERN DG Heuer ended the program by thanking everyone, and looking forward to the first run of LHC collisions at reasonable intensity with the detector magnets on (although only at 450 GeV), which is now scheduled for Saturday.

Update: Videos of the talks are now available here and I’ve watched a few of them. One interesting thing I noticed was Frank Wilczek’s talk about QCD, where his response to a question about AdS/CFT was “I’m not as impressed as I should be.”

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Sci-Fi Science

I watched the first two episodes of Michio Kaku’s Sci-Fi Science show last night (for a review, see here). The format of the show is that Kaku uses supposedly real physics to design on his laptop a revolutionary new device, then unveils it at the end of the show to a group of sci-fi fans for what I guess is supposed to be a form of peer review. The adoring fans are suitably impressed. In the first episode the device was a warp drive, in the second a portal to other universes, based on a big accelerator and “negative matter”. In both cases “negative energy” played a big part.

Neither episode involved a non-negligible amount of legitimate science, instead treating the physics in a completely misleading way. The second episode included participation by Max Tegmark, Alan Guth and Neil Turok. I wonder if they’ve seen the final product and what they think of it.

Posted in Uncategorized | 49 Comments

LHC at the High Energy Frontier

A few minutes ago, one of the beams of the LHC was ramped up to an energy of 1180 GeV, besting the Tevatron’s top beam energy of 980 GeV.

Update: Actually the beam was lost at 1040 GeV, which is still a record high energy.

Update: A few minutes ago both beams were successfully ramped up simultaneously to 1180 GeV.

Update: Wow, that was quick. First publication based on LHC data is now out, from ALICE, based on data gathered a week ago. Nothing at all unexpected, this is just based on 284 total events, at the already well-studied energy of 900 GeV.

Posted in Experimental HEP News | 18 Comments

One Reason Science is Having Trouble Banishing Religious Thinking

Andrew Sullivan, under the title String Theory and Miracles quotes part of a blog posting entitled One reason science is having trouble banishing religious thinking at the Democracy in America site (the original posting text is not there right now, may reappear) which notes that the spectacle of physicists widely promoting to the public the string theory multiverse is having the following effect:

It’s not always readily apparent to non-physicists why this kind of talk is less supernatural than a belief in the persistence of the soul after death….

But strictly in terms of how the argument between theists and atheists plays out in the public domain, there is a different quality to the tenets that are emerging on the atheistic, particle-physics side of things these days.

The string theory multiverse pseudo-science has done a huge amount of damage to the interests of string theory within the academic community, but it also threatens to do damage to the understanding and image of science among the public. Unfortunately, while there is more and more physics content in US popular media, it is often in the form of string theory-based pseudo-scientific nonsense rather than real science. For examples of this, see a new article in the Denver Post which catalogs some of this (while arguing that it’s a good thing):

TV is working through the shock of the age of terrorism and dismay at the broken boundaries of science, right before our eyes. Parallel universes? Bending time? Alternate dimensions? Some heavy-duty thoughts are seeping into prime time every week.

To the extent that TV reflects the culture at large, these shows seem to be saying we’re on the cusp of major change — technological, scientific, political or emotional. We may not have answers but we’re aware of expanding questions. In 2009, it has become accepted for folks on the couch to converse about the space-time continuum. Not that we understand string theory, but we recognize it when it pops up in TV scripts, peppering a spy thriller. “Lost” pushed the way with its dialogue about “moving the island,” leading fans to discuss time-shifting, wormholes and Einstein’s relativity theory.

Really.

The newer shows are picking up the string (theory) and running with it. There are hopeful signs in all this. The sci-fi series depict humans taking control of the planet, voting in favor of free will and standing up for the species. Maybe TV can provide some wishful thinking.

Posted in Uncategorized | 9 Comments

Short Items

  • To get an idea of what’s going on at CERN not at the LHC, but at the theoretical end of things, take a look at the presentations at the recent CERN-TH retreat.
  • I was worried that this blog marked the end of the distinguished series of publications of W. C. Gall. Fortunately, I see that there is now more.
  • A year ago I attended a talk at NYU by IAS director Peter Goddard on the early history of the IHES and how it was inspired by the Princeton Institute. Cormac O’Raifertaigh reports here on a recent talk by Goddard at the Dublin Institute of Advanced Studies, about how it too grew out of a similar inspiration.
  • Via Jordan Ellenberg, there’s news of a claimed proof of Leopoldt’s conjecture, with details available at a blog entry by Minhyong Kim at the new London Number Theory blog.
  • Among courses this semester the world over I wish I could attend, one would be Eckhard Meinrenken’s on Lie Groups and Clifford algebras. Luckily he’s producing lecture notes, updating those from a previous version of the course.
  • Next Tuesday the Science Channel will continue it’s great tradition of programming about fundamental physics with the premiere of a new show called Sci-Fi Science featuring Michio Kaku. The first evening’s episodes will explain

    a loophole in Einstein’s theory of relativity that shows how a spacecraft could travel at warp speed.

    followed by

    Dr. Kaku is on a mission to design a gateway to a parallel universe – but which type should he visit? MIT cosmologist Alan Guth explains his recipe for creating your own universe in the lab, and physicist Neil Turok explains how a parallel universe is only an atom’s length away from us.

    To their credit, sometimes they do actually have some real practical science which is not science fiction: yesterday they had Frank Wilczek on this show.

  • Update: Lubos has more Kaku.

    Posted in Uncategorized | 3 Comments

    First Collisions at the LHC

    Things evidently went extremely well over the weekend at the LHC, with simultaneous circulating beams achieved this morning. Speculation is that first collisions (at the injection energy of 450 GeV/beam) are imminent. Places for up to the minute information include here, here and here.

    Update: It looks like first collisions have been seen at the LHC. Announcement comes from a muzzled blogger….

    Update: Modified posting title.

    Update: For a series of talks about events during the first few days since beam injection at the LHC, see here. Progress was dramatic during the first few days, although it has slowed up recently. As data starts to come in, the first scientific task for the experiments is to re-discover the Standard Model. So far, CMS has managed to rediscover the pi-zero.

    Posted in Experimental HEP News | 13 Comments

    Higgs Escapes Part of Exclusion Region

    This past winter a combined analysis of data from the two Tevatron experiments showed at 95% confidence level that the Higgs mass could not be in the range 160-170 GeV. This was a better result than expected: statistically the experiments should not have been able to exclude any of the mass range, but were helped by a downward statistical fluctuation.

    Today a new and improved combined analysis was released using more data, and the new result is that there has been a reversion to the mean, no more help from statistical fluctuation downwards. Statistically, this time they should have been able to exclude 159-168 GeV, but now the fluctuation is a bit upwards, so the actual exclusion region is 163-166 GeV. In essence, better data has shown that the likelihood of a 160-163 or 166-170 GeV Higgs, something that was previously assigned a probability of a bit less than 5%, now has a probability a bit more than 5%. So, any putative Higgs particle in those mass regions has now escaped being tarred with the unfair label of “excluded”.

    If the Higgs is actually there at a certain mass, as one gets closer and closer to having sufficient data to exclude its existence, one should find oneself doing nowhere near as well as expected as far as excluding that mass. A thoroughly irresponsible person might see some significance in the fact that, unlike the analysis from earlier this year, the new improved analysis with more data does a worse job of exclusion than expected over much of the low mass range, peaking at 1.5 sigma or so for the mass range around 135 GeV.

    Update: More detail and rank speculation about this from Tommaso Dorigo here.

    Posted in Experimental HEP News | 5 Comments

    LHC Update

    Yesterday the LHC Hardware Commissioning Coordination Team announced the end of the 2009 Hardware Commissioning Campaign as all 8 LHC sectors were declared commissioned and ready for beam. A two day checkout period is now underway, which should have the LHC ready for beam at 17:00 Friday. Friday evening and night should see beams threaded around the machine in both directions. Saturday the plan is to capture a circulating beam in one direction, Sunday in the other direction. Celebratory drinks are scheduled for 17:00 Monday in the CERN Control Center.

    Update: Up-to-date news about beam commissioning is here, and hopefully CERN won’t shut off outside access to it. Normally I try and avoid providing links that might be in danger of becoming non-public, but in this case, since the New York Times is linking to this, I suppose I should too.

    Update: The LHC Portal is a site with a lot of links to CERN information. For more about the site, see here.

    Update: Beam is in the LHC and has made it part way around, to IP3. One place to follow progress is here.

    Just as I finished writing that, I see it’s now at IP5.

    Update: After a short stop to recover from a magnet quench, the beam has now gone all the way around the ring, making two turns.

    Posted in Experimental HEP News | 5 Comments

    A Brilliant Darkness

    Joao Magueijo has a new book out about Ettore Majorana, entitled A Brilliant Darkness. It’s a lot of fun to read, and could be described as an example of Gonzo history of science. While it contains a lot of factual information, much of which I was unaware of, it’s probably best to think of it like the works of Hunter S. Thompson. Not a good place to go for authoritatively accurate information about, e.g., Las Vegas or the 1972 US Presidential campaign, but a highly personal investigation that manages to get to the heart of the matter, finding emotional if not literal truth.

    For some examples, here’s Magueijo on Majorana’s upbringing:

    Jokes and pranks aside, one should not get the impression that Ettore’s youth was a happy one. It was dire. Between the priests and his parents, his basic humanity was destroyed. He was brought up by social outcasts and grew monstrously distorted, lacking social skills and independence, full of ineptitude. People like him — when they don’t become criminals, drug addicts or psychopaths — can’t help being intellectually superior. But they’re “Frankensteins,” artificially gifted, clever “against nature.” And like the literary monstor, behind the bestial genius lies a very different nature: tender in a way that can never be fully realized; longing for love, knowing full well that it will always be denied; a furnace of kind emotions that the ogre exterior will always screen.

    and here’s his account of his own trip on the ferry where Majorana presumably killed himself in 1938 at the age of 31:

    Back on deck, I realize what a gloomy figure I must cut: pensive and stark, staring at the sea. Maybe the insomniac brigade is worried I might be contemplating suicide. A girl comes out to smoke and waits to be chatted up. I move to the rear. What a sad bastard I must look, refusing to play the game of life, shouting and fucking, throwing up against the wind. I watch the wake for a long time, the cigarette butts flying past me into the night, like fireflies from Mars. In our world of the “normal”, anyone who thinks is likely to appear suicidal. And yet, suicide or not, we will all be there one day, not just Ettore. We are all the same, only in different seasons.

    Majorana was born in 1906 in Sicily, went to Rome for his studies. His career as a physicist basically spanned just the years 1928-1933, much of which was spent working in Fermi’s famous group in Rome. For Magueijo, Fermi is one of the villains of the piece, with Majorana a genius much his superior. Unlike the rest of the group, Majorana wasn’t interested in experimental work, nor much interested in publishing his ideas, about which Magueijo claims:

    That’s how he never got credit for Heisenberg’s theory of nuclear forces and the neutron, the Weisskopf-Pauli second quantization of the complex scalar field, or the parity-violating properties of the neutrino, which earned Tsung Dao Lee and Chen Ning Yang the Nobel Prize some thirty years later. They could all have been named after Majorana. But because he never published his work, only the Majorana neutrino — his inseparable soul mate — carries Ettore’s name today.

    In 1933 Majorana traveled to Leipzig to work with Heisenberg, then to Copenhagen to work with Bohr. When he returned to Rome, some combination of physical and mental health problems led him to become a recluse for several years. He emerged from this state in 1937 to take up a professorship in Naples, but a few months later disappeared after embarking on a ferry taking him from Palermo back to Naples.

    Majorana’s most important scientific work appeared in a 1932 Nuovo Cimento paper motivated by the desire to find a replacement for the Dirac equation that would solve the problem of its negative energy states (a problem which disappeared in 1932 with the discovery of the positron). In this paper, Majorana investigated for the first time infinite dimensional representations of the Lorentz group, ones whose role in physics, if any, remains mysterious. As part of this work, he discovered the possibility of a real representation of the Clifford algebra and thus a version of the Dirac equation in which a particle is its own anti-particle. Whether this possibility is realized in the case of neutrinos is one of the big open questions of the subject. We know that there must be neutrino mass terms, but we don’t know if they’re of Majorana or Dirac form.

    [Note added: There are actually two papers here, both of which appear to have been completed in 1932, but the second one was only published in 1937, when Majorana was applying for the professorship in Naples. The 1932 paper is concerned with his infinite component wave equation. It’s only in the 1937 paper that the real representation of the gamma-matrices and what is now known as the “Majorana neutrino” make their appearance.]

    Magueijo does a good job of describing this important physics at a popular level. He also gives a lot of space to the various myths that have grown up around the story of Majorana’s disappearance. There’s a whole subculture out there devoted to them. He wisely decides not to sign on to any of these or create his own, concluding:

    And as with the neutrino, Ettore’s story is also elusive. Even if we found out for sure what actually happened to him, we’d never know why he did it — which is far more important. This absence of a final truth shouldn’t sadden us: At leas we don’t harbor delusions of omniscience. When I got on that plane to Sicily, I promised myself only this: I won’t raise my leg and urinate over my little territory in Ettoreland; I won’t invent a solution that is not needed.

    Posted in Book Reviews | 11 Comments