Physics

According to a new model, galaxies may contain disks made of a specific type of dark matter that can interact more strongly than most dark matter. Published Thu May 23, 2013
According to a new model, galaxies may contain disks made of a specific type of dark matter that can interact more strongly than most dark matter. Published Thu May 23, 2013
about 5 hours ago
Transitions in an atom can allow nondestructive measurement of the quantum vacuum state. Published Thu May 23, 2013
Transitions in an atom can allow nondestructive measurement of the quantum vacuum state. Published Thu May 23, 2013
about 5 hours ago
A quantum gravity theory suggests that the cores of black holes may be a region of highly curved spacetime, rather than a singularity point with zero volume and infinite density. Published Thu May 23, 2013
A quantum gravity theory suggests that the cores of black holes may be a region of highly curved spacetime, rather than a singularity point with zero volume and infinite density. Published Thu May 23, 2013
about 5 hours ago
Upgrades to the Facility for Advanced Accelerator Experimental Tests—including a new 10-terawatt laser—will assist in R&D for new methods of particle acceleration. Just over a year after opening its beam to researchers fro...
Upgrades to the Facility for Advanced Accelerator Experimental Tests—including a new 10-terawatt laser—will assist in R&D for new methods of particle acceleration. Just over a year after opening its beam to researchers from around the world, the Facility for Advanced Accelerator Experimental Tests (FACET) at SLAC is shining a little brighter. With the addition of a new 10-terawatt laser and other equipment upgrades, one of the facility’s main goals—the development of a new method of particle acceleration that boosts particles’ energy on waves of plasma—looks especially promising.
about 8 hours ago
Two hungry young galaxies that collided 11 billion years ago are rapidly forming a massive galaxy about 10 times the size of the Milky Way, according to UC Irvine-led research published Wednesday in the journal Nature.... UC I...
Two hungry young galaxies that collided 11 billion years ago are rapidly forming a massive galaxy about 10 times the size of the Milky Way, according to UC Irvine-led research published Wednesday in the journal Nature.... UC Irvine Media Realease. (2013) Fragile mega-galaxy is missing link in history of cosmos. UC Irvine. info:/
about 11 hours ago
A book on the various roles that electricity plays in the human body, reviewed by Richard Clayton
A book on the various roles that electricity plays in the human body, reviewed by Richard Clayton
about 12 hours ago
Brian Cox's venture into the life sciences and a travel guide to the Northern Lights reviewed by Margaret Harris and Tushna Commissariat
Brian Cox's venture into the life sciences and a travel guide to the Northern Lights reviewed by Margaret Harris and Tushna Commissariat
about 12 hours ago
This week on the podcast I chat with Diandra Leslie-Pelecky, a physicist at West Virginia University and the author of The Physics of NASCAR. What on earth does NASCAR have to do with physics? Everything. From the banking of the turns to...
This week on the podcast I chat with Diandra Leslie-Pelecky, a physicist at West Virginia University and the author of The Physics of NASCAR. What on earth does NASCAR have to do with physics? Everything. From the banking of the turns to the design of the rear-view mirrors, physics is what makes NASCAR possible. And NASCAR has also proved to be a laboratory for new physics insights. Take the phenomenon of drafting, in which one car driving behind another can get a boost in speed from the front car's wake. Cyclists take advantage of this, as do birds. Drivers and team members spotted the change immediately, although they couldn't explain exactly why it was happening (and the exact explanation was left up to physicists to figure out). They started testing this phenomenon in practice, and worked out how they could use it to their benefit during races. This practice of observation and testing is also the basis of the scientific method. To hear more about the physics of NASCAR, listen in to this week's podcast. You can also hear Diandra on the radio show SiriusXM Speedway, where she appears regularly to help debunk myths about the science of NASCAR (like whether or not the cars speed up when they go from the track to the grass).
about 23 hours ago
In recent years there have been many claims made for “evidence” of a multiverse, supposedly found in the CMB data (see for example here). Such claims often came with the remark that the Planck CMB data would convincingly dec...
In recent years there have been many claims made for “evidence” of a multiverse, supposedly found in the CMB data (see for example here). Such claims often came with the remark that the Planck CMB data would convincingly decide the matter. When the Planck data was released two months ago, I looked through the press coverage and through the Planck papers for any sign of news about what the new data said about these multiverse evidence claims. There was very little there; possibly the Planck scientists found these claims to be so outlandish that it wasn’t worth the time to look into what the new data had to say about them. One exception was this paper, where Planck looked for evidence of “dark flow”. They found nothing, and a New Scientist article summarized the situation: “The Planck team’s paper appears to rule out the claims of Kashlinsky and collaborators,” says David Spergel of Princeton University, who was not involved in the work. If there is no dark flow, there is no need for exotic explanations for it, such as other universes, says Planck team member Elena Pierpaoli at the University of Southern California, Los Angeles. “You don’t have to think of alternatives.” One of those promoting the idea that “dark flow” was evidence for a multiverse was Mersini-Houghton, who in a 2008 paper with Holman wrote: Our contention, then, is that these observations of bulk flow can be construed as evidence for the birth of the universe from the landscape multiverse imprinted on the superhorizon sized nonlocal quantum entanglement between our horizon patch and others that began from the landscape. When we calculate the size of the induced dipole in our theory and convert it into a bulk velocity dispersion, we will see that for the constrained values of our parameters we arrive at a velocity dispersion of order 670 km/sec, remarkably close to the observed value of 700 km/sec. One might think that the refutation of their prediction by the Planck data would be a problem. Instead though, the Sunday Times reported a few days ago that Scientists believe they have found the first evidence that other universes exist. The story got picked up by other news outlets, and appeared in the Daily Mail as “The first ‘hard evidence’ that other universes exist has been found by scientists”. The source for the story was Mersini-Houghton: Laura Mersini-Houghton, theoretical physicist at the University of North Carolina at Chapel Hill, and Richard Holman, professor at Carnegie Mellon University, predicted that anomalies in radiation existed and were caused by the pull from other universes in 2005. Now that she has studied the Planck data, Dr Mersini-Houghton believes her hypothesis has been proven. Her findings imply there could be an infinite number of universes outside of our own. She said: ‘These anomalies were caused by other universes pulling on our universe as it formed during the Big Bang. ‘They are the first hard evidence for the existence of other universes that we have seen.’ She will be in Britain soon promoting this at the Hay Festival on June 31 and at Oxford on June 11. According to a New Scientist story just out, this hard evidence for the multiverse should be welcomed, since it (together with string theory) has just been shown to have the power to save us from “Legions of disembodied brains floating in deep space”. The story, which appeared in print as String Theory Limits Space Brain Threat starts with LEGIONS of disembodied brains floating in deep space threaten to undermine our understanding of the universe. New mathematical modelling suggests string theory and its multiple universes may just provide our salvation – and that could win the controversial theory a few more backers. It goes on to explain about Boltzmann brains and a recent paper by Bousso and Zukowski, and ends with news of yet another expe
about 24 hours ago
Ancient collision could explain why some young galaxies look old
Ancient collision could explain why some young galaxies look old
1 day ago