Physics

“…an understanding of the infinite tree of universes seems to be needed in order to make statistical predictions about the properties of our own universe, which is assumed to be a typical “branch” on the tree.” -Alan Guth The Big Bang is commonly regarded as the start of it all, but that's only the birth of what we call our observable Universe. There must have been something compelling to set it up, complete with the initial conditions that our Universe began with. An idea called Cosmic Inflation fits the bill perfectly, providing those conditions and making six explicitly new predictions.…

"When we have found how the nucleus of atoms is built up we shall have found the greatest secret of all — except life." -Ernest Rutherford What does the future of astrophysics look like? Have we already made all of the fundamental discoveries we’re going to make? Is the rest just categorization of objects, identification of more examples of what’s already known, and minor refinements of the knowledge we already have? Or are there fundamental discoveries still to come, just waiting for us to reveal them? The four possible fates of our Universe into the future; the last one appears to be the…

"Two recent studies by teams in the U.S. and the Netherlands have shown that the gamma-ray excess at the galactic center is speckled, not smooth as we would expect for a dark matter signal. Those results suggest the speckles may be due to point sources that we can’t see as individual sources..." -Eric Charles When NASA’s Fermi satellite began operations, it didn’t take long before we had constructed the most accurate, comprehensive gamma ray map of the galaxy. While many outstanding astrophysics findings ensued, including the discovery of many new pulsars, there was one particular mystery…

"We have never observed infinity in nature. Whenever you have infinities in a theory, that's where the theory fails as a description of nature. And if space was born in the Big Bang, yet is infinite now, we are forced to believe that it's instantaneously, infinitely big. It seems absurd." -Janna Levin You’ve likely heard that there’s no sound in space; that sound needs a medium to travel through, and in the vacuum of space, there is none. That’s true... up to a point. If you were only a few light years away from a star, stellar remnant, black hole, or even a supernova, you’d have no way to…

"Whether humans are responsible for the bulk of climate change is going to be left to the scientists, but it's all of our responsibility to leave this planet in better shape for the future generations than we found it." -Mike Huckabee It only makes sense that scientists should debate and argue over the findings in their field. Given all the suites of data available that are relevant to a particular physical phenomenon, how do we put it together in a way that is scientifically robust, allow us to understand and predict what’s happening, and justifiably attribute the causes of observed…

“Time travel used to be thought of as just science fiction, but Einstein's general theory of relativity allows for the possibility that we could warp space-time so much that you could go off in a rocket and return before you set out.” -Stephen Hawking As always, there's been a new fantastic week of articles here at Starts With A Bang, punctuated by our new podcast this month, on the physics of time travel! Have a listen (or download it and take it with you) and thank our Patreon supporters for making it possible! Now, what was this past week all about? Come enjoy some fabulous stories if…

"One of the great things about music is that it has the capability of time travel - you smell a certain smell in the room and it takes you back to your childhood. I feel like music is able to do that, and it happens to me all the time." -M. Ward Have you ever wondered about time travel? Perhaps you have your destination in the far future, and want to see how it all turns out? Maybe you want to return to the past, and alter the future or present by your actions there? Or maybe you want to freeze time altogether? If you want to know whether it's possible, the physics of relativity holds the…

"The experiments that we will do with the LHC [Large Hadron Collider] have been done billions of times by cosmic rays hitting the earth. ... They're being done continuously by cosmic rays hitting our astronomical bodies, like the moon, the sun, like Jupiter and so on and so forth. And the earth's still here, the sun's still here, the moon's still here." -John Ellis Relativity, or the idea that space and time are not absolute, was one of the most revolutionary and counterintuitive scientific theories to come out of the 20th century. It was also one of the most disputed, with hundreds of…

"It appears, from all that precedes, reasonably certain that if there be any relative motion between the earth and the luminiferous ether, it must be small; quite small enough entirely to refute Fresnel's explanation of aberration." -Albert A. Michelson In the 1880s, it was clear that something was wrong with Newton’s formulation of the Universe. Gravitation didn’t explain everything, objects behaved bizarrely close to the speed of light, and light was exhibiting wave-like properties. But surely, even if it were a wave, it required a medium to travel through, just like all other waves? That…

"In recent years several new particles have been discovered which are currently assumed to be “elementary,” that is, essentially structureless. The probability that all such particles should be really elementary becomes less and less as their number increases. It is by no means certain that nucleons, mesons, electrons, neutrinos are all elementary particles." -Enrico Fermi The Standard Model of particle physics -- with its six quarks in three colors, its three generations of charged leptons and neutrinos, the antiparticle counterparts to each, and its thirteen bosons, including the Higgs --…

"We must regard it rather as an accident that the Earth (and presumably the whole solar system) contains a preponderance of negative electrons and positive protons. It is quite possible that for some of the stars it is the other way about." -Paul Dirac You might think that the proton, made up of three spin=1/2 quarks, has a spin of 1/2 for that exact reason: you can sum three spin=1/2 particles together to get 1/2 out. But that oversimplified interpretation ignores the gluons, the sea quarks, the spin-orbit interactions of the component particles. Most importantly, it ignores the experimental…

"You couldn’t be here if stars hadn’t exploded, because the elements - the carbon, nitrogen, oxygen, iron, all the things that matter for evolution and for life - weren’t created at the beginning of time. They were created in the nuclear furnaces of stars, and the only way for them to get into your body is if those stars were kind enough to explode..." -Lawrence Krauss Throughout the 1940s, 50s and even 60s, a debate as to the origin of the Universe raged in astrophysics. Was the Big Bang theory, where the Universe emerged from a hot, dense state some finite time ago, or the Steady-State…

"Entropy shakes its angry fist at you for being clever enough to organize the world." -Brandon Sanderson The universe was born hot, dense, expanding, full of matter, antimatter and radiation... and in a low-entropy state. If entropy is a measure of disorder, though, that sure does sound like an awfully high-entropy state, not a low-entropy one. So why, when we talk about the Universe, do we say that the early Universe had such low entropy? Our Universe, from the hot Big Bang until the present day, underwent a huge amount of growth and evolution, and continues to do so. Image credit: NASA /…

“There is a fifth dimension, beyond that which is known to man. It is a dimension as vast as space and as timeless as infinity. It is the middle ground between light and shadow, between science and superstition.” -Rod Serling If we take a look at a two-dimensional surface, it’s pretty apparent that we’re pretty omnipotent in comparison. We can draw or erase anything in that dimension, add or remove objects, rearrange their internal structures without leaving them any defense, etc. All of that might lead you to wonder whether there’s the possibility of a fourth spatial dimension out there, and…

"I do have a blurred memory of sitting on the stairs and trying over and over again to tie one of my shoelaces, but that is all that comes back to me of school itself." -Roald Dahl Most of us learn to tie our shoes when we’re very young, go through life tying it through that very same method, and never think about it again. Yet for some of us, routinely untied shoelaces are a part of our daily lives, while for others, our shoes rarely come undone, even without double-knotting them. The reason for this is twofold: one is the way we wear our shoes, but the other is the way we tie them. The…

"I would like nuclear fusion to become a practical power source. It would provide an inexhaustible supply of energy, without pollution or global warming." -Stephen Hawking Climate science is a hotly debated area, with many disputing the robustness and ethical motivations of the scientists in the field. But even if you throw everything we know about carbon dioxide, global warming, and climate change away, there’s still an energy crisis coming in the long term. The fact is, fossil fuels will someday, hundreds of years from now, run out if we extract and burn them all. Wind farms, like many…

“There is a fine line between censorship and good taste and moral responsibility.” -Stephen Spielberg Another week full of amazing science stories has gone by here at Starts With A Bang, and there are some fun and fantastic announcements! We welcomed a new contributor, Jess Shanahan, to our ranks; I found out that Forbes has made me their official Star Trek: Discovery reviewer when that new series premieres; I'm in the process of selecting the final, officially licensed images for my new book, Treknology (and pre-order today!); and from this coming Thursday through Sunday, I'll be the Science…

"There is a limit on how much information you can keep bottled up." -Dick Gregory There are fundamental limits to the Universe, in the sense that there are scales where our laws of physics break down. You can't break matter or energy up into infinitely small pieces, and the same goes -- we think -- for space and time. But is that necessarily all true, and is that what the Planck scale means? Not quite. Although X-ray observations have set limits on the granularity of space, they have not probed anywhere near down to the Planck scale. Image credit: X-ray: NASA/CXC/FIT/E. Perlman; Illustration…

"It does not matter how slowly you go as long as you do not stop." -Confucius The large hadron collider is the world’s most powerful particle accelerator, colliding two protons at energies of 6.5 TeV apiece. But you’ll never have the full 13 TeV of energy available for that collision, thanks to the fact that the proton itself is a composite particle, and that energy is distributed throughout its components. When you get a collision, only a fraction of that energy goes into the collision itself, while the rest remains in the other component particles. A candidate Higgs event in the ATLAS…

Another month, another batch of blog posts at Forbes: -- In Physics, Infinity Is Easy But Ten Is Hard: Some thoughts on the odd fact that powerful math tricks make it easy to deal uncountably many interacting particles, while a smaller number would be a Really Hard Problem. -- New Experiment Explores The Origin Of Probabilities In Quantum Physics: A write-up of an experiment using a multi-path interferometer to look for departures from the Born rule for calculating probabilities from wavefunctions. -- The Most Important Science To Fund Is The Hardest To Explain: In light of the awful budget…