We have a space station in permanent orbit … but not a lot of rockets that can get there. On the assumption that the free market can blast us to the ISS on the cheap, NASA has awarded resupply contracts to two private companies, Orbital Sciences and SpaceX. But the two space ferries have some key differences, and the competition between them is shaping up to be a dogfight between reliable spaceships of the past and slick ones from the future. Here’s how they line up.
In quite an eerie feat, physicists have floated microscopic diamonds in midair using laser beams.
Researchers have already used lasers to levitate extremely small particles, such as individual atoms, but this is the first time that the technique has worked on a nanodiamond, which, in this case, measures just 100 nanometers (3.9 x 10-8 inches) across, or more than 1,000 times thinner than a fingernail.
In the new study, the physicists from the University of Rochester relied on the fact that a laser beam, which is made up of photons, creates a tiny force that usually can’t be felt.
"If we turn on a light or open a door and feel the sun, we don’t feel this push or pull," study researcher Nick Vamivakas said in a video released by the university. "But it turns out that if you focus a laser down with a lens to a very small region of space, it can actually pull on microscopic, nanoscopic particles."
To force the tiny diamonds to float, Vamivakas and his colleagues focused a pair of lasers toward a clear vacuum chamber and then sprayed the diamonds into the chamber using an aerosol dispenser. The diamonds gravitated toward the light, and some eventually levitated in a stable position.
Sometimes, the levitation occurred within just a couple of minutes, while other times, the process took a bit longer. “Other times, I can be here for half an hour before any diamond gets caught,” Levi Neukirch, a graduate student at the University of Rochester who was involved in the study, said in a statement. “Once a diamond wanders into the trap, we can hold it for hours.”
The team hopes the findings will have applications in quantum computing and, more theoretically, help explain how friction operates on extremely small scales.
Even if you’re not Edward Snowden, there are times when excising your social media presence is necessary. Companies usually don’t make it easy, though, often hiding the delete button inside myriad confusing menus and settings. Save some time and bookmark justdelete.me, a new page that collects direct links for killing various accounts dead and puts them all on one, easy-to-use page.
Justdelete.me is an excellent resource and evidently quite a bit of work went into it. For instance, for Facebook, the link goes directly to the delete button (no “deactivation” shenanigans here.) But not all accounts are as simple: Sometimes you’ve got to contact customer service, or, like Netflix, they’ll cancel your account but won’t delete your data. Even here justdelete.me excels, linking to the relevant help pages and contact forms.
Give Robb Lewis the good Netizen of the month award. Although most competent computer users could eventually find all these various methods to delete online accounts, it’s quite a bit faster (and less frustrating) when they’re all on one page. He even put the source for justdelete.me on Github too — so if he loses interest or the various social media companies change their policies, this killer idea can live on.
New research from Japan has suggested that it may be possible in the future for scientists to grow male and female reproductive cells from the opposite gender. In other words, to create sperm from women and eggs from men. Japanese researchers use skin cells from mice to create sperm and eggs that were later used to create a live birth.
Katsuhiko Hayashi of Kyoto University in Japan has published research in which skin cells from mice were used to create primordial germ cells or PGCs. These cells, the common precursor of both male and female sex cells, were then developed into both sperm and eggs. Using these live-births were created via in vitro fertilisation.
Although the techniques involved are still in their infancy, the possibilities for reproductive medicine are startling. Not only could the research of Hayashi and his senior professor Mitinori Saitou allow infertile women to have babies by creating eggs from their skin cells, but it might make it possible for sperm and eggs cells to be created from either males or females.
The process begins by extracting pluripotent stem cells from early-stage embryos and somatic cells, and then converting these into PGCs using ‘signalling molecules’. These germ cells were transplanted into the ovaries and testes of living mice to develop. Once these cells were mature they were extracted and used to fertilise one another in vitro.
Are black holes surrounded by walls of fire? Does this imply that one (or more) of our most cherished physical principles–and here I’m talking about biggies like quantum theory, the conservation of information or Einstein’s equivalence principle–is wrong? Any may our savior come in the form of wormholes? These are the questions consuming some of the world’s foremost theoretical particle physicists as they argue about potential solutions to what has become known as the “black hole firewall” problem–perhaps the most important paradox in physics since Stephen Hawking proposed his first black hole information paradox nearly four decades ago.
The black hole firewall paradox has caused no small amount of wonder and confusion amongst particle physicists. It appears as though one of our core beliefs about the universe is wrong: Either particles can be promiscuously entangled, leading to quantum disaster (basically no one takes this option seriously; quantum theory and the no-promiscuous-entanglement rule are far too well supported by decades of experimental evidence), or information is not conserved (another non-starter), or black holes have firewalls (even Polchinski considers this a reductio ad absurdum), or… we just don’t fully understand what’s really going on.
And so in an effort to sort the mess out, physicists gathered this week at the Kavli Institute for Theoretical Physics at UCSB to talk over the options. One of the most intriguing possibilities for a solution comes from Juan Maldacena and Leonard Susskind, building on the ideas of Mark Van Raamsdonk and Brian Swingle. Maldacena and Susskind posit that the solution to the firewall problem may come in the form of wormholes.
Wormholes are theoretical objects that connect two different points in space. They’re allowed as possible solutions to Einstein’s equations for general relativity–indeed, Einstein and his colleague Nathan Rosen first discovered wormholes, which is why they’re also called Einstein-Rosen bridges. Unfortunately, wormholes aren’t perfect–Einstein’s equations also imply that nothing with nonnegative energy (that is to say: nothing that we know of) can traverse a wormhole, so they’re not going to make for useful intergalactic portals anytime soon.
Maldacena and Susskind, following Van Raamsdonk, posit that any time two quantum particles are entangled, they’re connected by a wormhole. They then go on to say that the wormhole connection between particles inside a black hole (the infalling virtual particles) and the particles outside of a black hole (the Hawking radiation) soothes out the entanglement problems enough so that we can avoid the firewall at the event horizon.
Note that this requires a profound rethinking of the fundamental stuff of the universe. Entanglement, a deeply quantum phenomenon, is fundamentally wound into to the geometry of the universe. Or, to flip it around, quantum weirdness may be stuff that creates the substrate of spacetime.
Of course, nothing is settled yet. As Maldacena and Susskind write towards the end of their paper: “At the moment we do not know enough about Einstein-Rosen bridges involving clouds of Hawking radiation to come to a definite conclusion…. The AMPS paradox is an extremely subtle one whose resolution, we believe, will have much to teach us about the connection between geometry and entanglement. AMPS pointed out a deep and genuine paradox about the interior of black holes.”
And if there’s one great thing about paradox, it’s that their resolutions require radical breakthroughs. The equipment we build for the job may take us to places we’ve never dreamed.
An international group of scientists has shown that a drug candidate designed by scientists from the Florida campus of The Scripps Research Institute (TSRI) significantly increases exercise endurance in animal models.
These findings could lead to new approaches to helping people with conditions that acutely limit exercise tolerance, such as obesity, chronic obstructive pulmonary disease (COPD) and congestive heart failure, as well as the decline of muscle capacity associated with aging.
The study was published July 14, 2013, by the journal Nature Medicine.
The drug candidate, SR9009, is one of a pair of compounds developed in the laboratory of TSRI Professor Thomas Burris and described in a March 2012 issue of the journal Nature as reducing obesity in animal models. The compounds affect the core biological clock, which synchronizes the rhythm of the body’s activity with the 24-hour cycle of day and night.
The compounds work by binding to one of the body’s natural molecules called Rev-erbα, which influences lipid and glucose metabolism in the liver, the production of fat-storing cells and the response of macrophages (cells that remove dying or dead cells) during inflammation.
In the new study, a team led by scientists at the Institut Pasteur de Lille in France demonstrated that mice lacking Rev-erbα had decreased skeletal muscle metabolic activity and running capacity. Burris’ group showed that activation of Rev-erbα with SR9009 led to increased metabolic activity in skeletal muscle in both culture and in mice. The treated mice had a 50 percent increase in running capacity, measured by both time and distance.
“The animals actually get muscles like an athlete who has been training,” said Burris. “The pattern of gene expression after treatment with SR9009 is that of an oxidative-type muscle— again, just like an athlete.”
The authors of the new study suggest that Rev-erbα affects muscle cells by promoting both the creation of new mitochondria (often referred to as the “power plants” of the cell) and the clearance of those mitochondria that are defective.
MIT’s definition of a breakthrough is simple: an advance that gives people powerful new ways to use technology. It could be an intuitive design that provides a useful interface (e.g., “Smart Watches”) or experimental devices that could allow people who have suffered brain damage to once again form memories (“Memory Implants”). Some could be key to sustainable economic growth (“Additive Manufacturing” and “Supergrids”), while others could change how we communicate (“Temporary Social Media”) or think about the unborn (“Prenatal DNA Sequencing”). Some are brilliant feats of engineering (“Baxter”), whereas others stem from attempts to rethink longstanding problems in their fields (“Deep Learning” and “Ultra-Efficient Solar Power”). As a whole, this annual list not only tells you which technologies you need to know about, but also celebrates the creativity that produced them.
In the never-ending quest to get computers to process, really understand and actually reason, scientists at Defense Advanced Research Projects Agency want to look more deeply into how computers can mimic a key portion of our brain.
The military’s advanced research group recently put out a call, or Request For information, on how it could develop systems that go beyond machine learning, Bayesian techniques, and graphical technology to solve “extraordinarily difficult recognition problems in real-time.”
Current systems offer partial solutions to this problem, but are limited in their ability to efficiently scale to larger more complex datasets, DARPA said. “They are also compute intensive, exhibit limited parallelism, require high precision arithmetic, and, in most cases, do not account for temporal data. “
What DARPA is interested in is looking at mimicking a portion of the brain known as the neocortex which is utilized in higher brain functions such as sensory perception, motor commands, spatial reasoning, conscious thought and language. Specfically, DARPA said it is looking for information that provides new concepts and technologies for developing what it calls a “Cortical Processor” based on Hierarchical Temporal Memory.
"Although a thorough understanding of how the cortex works is beyond current state of the art, we are at a point where some basic algorithmic principles are being identified and merged into machine learning and neural network techniques. Algorithms inspired by neural models, in particular neocortex, can recognize complex spatial and temporal patterns and can adapt to changing environments. Consequently, these algorithms are a promising approach to data stream filtering and processing and have the potential for providing new levels of performance and capabilities for a range of data recognition problems," DARPA stated. "The cortical computational model should be fault tolerant to gaps in data, massively parallel, extremely power efficient, and highly scalable. It should also have minimal arithmetic precision requirements, and allow ultra-dense, low power implementations."
The new RFI is only part of the research and development DARPA has been doing to build what it calls a new kind of computer with similar form and function to the mammalian brain. Such artificial brains would be used to build robots whose intelligence matches that of mice and cats, DARPA says.
Recently IBM said it created DARPA-funded prototype chips that could mimic brain-like actions. The prototype chips will give mind-like abilities for computers to make decisions by collating and analyzing immense amounts of data, similar to humans gathering and understanding a series of events, Dharmendra Modha, project leader for IBM Research told the IDG News Service. The experimental chips, modeled around neural systems, mimic the brain’s structure and operation through silicon circuitry and advanced algorithms.
IBM hopes reverse-engineering the brain into a chip could forge computers that are highly parallel, event-driven and passive on power consumption, Modha said. The machines will be a sharp departure from modern computers, which have scaling limitations and require set programming by humans to generate results.
Like the brain, IBM’s prototype chips can dynamically rewire to sense, understand and act on information fed via sight, hearing, taste, smell and touch, or through other sources such as weather and water-supply monitors. The chips will help discover patterns based on probabilities and associations, all while rivaling the brain’s compact size and low power usage, Modha said.
Physics students from the University of Leicester have calculated the time and energy required to beam a complete person from the Earth’s surface to a location in space. Their results were discouraging, to say the least.
Teleportation, or beaming, has long been a staple of science fiction. As anyone who’s seen Star Trek or The Fly knows, teleportation describes a hypothetical mode of near-instantaneous transportation in which matter is dematerialized at one place and reconsructed at another. The particular scheme that’s often employed in scifi is what’s called “destructive copying,” meaning that a source person is scanned and copied down to the molecular level and then reconstituted at a secondary location.
Neverminding the fact that this sort of teleportation strategy would serve as a veritable suicide machine (the source person would be destroyed during the copying procedure, as evidenced in the TNG episode, “Second Chances” when an ‘extra’ Riker was accidently created), the energy and bandwidth required to pull off such a feat would be astronomical. What’s more, due to the sensitivity of the transfer, the potential for catastrophic accidents would be significant.
For their analysis, the students assumed that a person would be beamed from the surface of the Earth to a location in orbit directly above it. Their first task was to figure out how much data constitutes a person — which is easier said than done. This is an area of great contention as we’re not entirely sure what level of granularity is required to capture a person’s complete essence. Is is the cellular level? Molecular? Atomic? Indeed, would we be the ‘same’ person if even a few atoms in the brain were out of place?
The students settled on the idea that transferable data could be represented by the DNA pairs that make up genomes in each cell. Each human cell was calculated to contain about 10 billion bits of information. They also assumed that each cell contains enough information to replicate any other type of cell in the body. After calculating the amount of information encapsulated in a typical human brain, the total data content was shown to be 2.6x10E42 bits. That’s a big staggering number!
Now, the trick is to transfer all that information — and quickly. In Star Trek, it takes about two to three seconds. But in reality, it would take considerably more. Assuming a bandwidth rate of about 29 to 30 GHz (a somewhat conservative figure based on current technologies), it would take 4.85x10E15 years. That’s 350,000 times longer than the current age of the Universe!
‘Current data transmission techniques’ being the key phrase, here. Humanity’s demand for energy is growing at an astonishing rate. In future, we may be able to increase throughput considerably by devising more powerful energy sources, and/or by transmitting the data along multiple parallel streams (like a data torrent). We could also employ data compression schemes to limit the amount of information that has to be transferred. For example, we could limit transfers to neural information only; a cyborg body could await the traveller at the destination, which would in turn produce all the bio-chemicals required for normal cognitive function (e.g. neurotransmitters).
So, yes — teleportation is certainly implausible by today’s standards — but it’s still not beyond the realm of theoretic possibility.