May 13, 2013 at 2:26 am #7360
The international system of units (SI) comprises seven base units (the metre, kilogram, second, Kelvin, ampere, mole and candela). Ideally these should be stable over time and universally reproducible. This requires definitions based on fundamental constants of nature which are the same wherever you measure them.
The present definition of the Ampere, however, is vulnerable to drift and instability. This is not sufficient to meet the accuracy needs of present and certainly future electrical measurement. The highest global measurement authority, the Conférence Générale des Poids et Mesures, has proposed that the ampere be re-defined in terms of the electron charge.
The frontrunner in this race to redefine the ampere is the single-electron pump (SEP). SEPs create a flow of individual electrons by shuttling them in to a quantum dot — a particle holding pen — and emitting them one at a time and at a well-defined rate. The paper published today describes how a graphene SEP has been successfully produced and characterised for the first time, and confirms its properties are extremely well suited to this application.May 13, 2013 at 11:56 am #7363
Re vacuum is not empty and the field fluctuations:
The dimensions of the simulation “box” is about the size of two protons. And the frame rate of the simulation is 1,000,000,000,000,000,000,000,000 frames per second.
“So where are you most likely to find a quark? Well, it turns out that the quarks like to sit on top of those lumps.”June 2, 2013 at 9:11 am #7476
Open questions in physics
While for the most part a FAQ covers the answers to frequently asked questions whose answers are known, in physics there are also plenty of simple and interesting questions whose answers are not known. Here we list some of these. We could have called this section Frequently Unanswered Questions, but the resulting acronym would have been rather rude.June 2, 2013 at 10:45 am #7478
I love reading physics forums.
Question:”Could anyone explain quantum fluctuation?”
What’s more, such quantum fluctuations in otherwise empty space are the tip of a very big iceberg that lies right at the frontier of one of the biggest white elephants sitting in the living room of modern physics. The influence of these fluctuations can be calculated using some rather mysterious yet effective mathematical approaches (called “renormalization”), resulting in successful predictions like the “Lamb shift” in the spectrum of hydrogen. So we may think of these vacuum fluctuations as “real things”, in that they have measurable consequences. However, there is a fly in the ointment (or more like a Mothra), which is that if one naively adds up the energy, however fleeting, associated with these fluctuations, the answer one comes to is infinite (by some accounts) or 120 orders of magnitude larger than anything that makes sense (by other accounts). So just underneath one of the most successful predictions of quantum electrodynamics, we have the all-time record for a wrong prediction (OK, it’s tied with the “ultraviolet catastrophe”).
In the past, this problem was swept under the rug by imagining that some missing physics or subtle mathematics insures that this huge or infinite sum actually adds up to zero, but now with “dark energy” and the accelerating universe, a popular alternative is that it adds up to something very small but not zero. But this presents an even harder challenge: if it seemed hard to get infinity to add up to zero, it seems harder still to get it to add up to something small but nonzero! It is possible that there is some future revolution in physics awaiting the answer to this question.June 2, 2013 at 10:54 am #7479
Since he mentions the UV catastrophe
According to classical electromagnetism, the number of electromagnetic modes in a 3-dimensional cavity, per unit frequency, is proportional to the square of the frequency. This therefore implies that the radiated power per unit frequency should follow the Rayleigh–Jeans law, and be proportional to frequency squared. Thus, both the power at a given frequency and the total radiated power is unlimited as higher and higher frequencies are considered: this is clearly unphysical as the total radiated power of a cavity is not observed to be infinite, a point that was made independently by Einstein and by Lord Rayleigh and Sir James Jeans in the year 1905.June 2, 2013 at 12:52 pm #7480June 2, 2013 at 2:07 pm #7481
Are we living in a black hole?
Every black hole contains a new universe…
Successful as it is, there are notable unsolved questions with the standard big bang theory, which suggests that the universe began as a seemingly impossible “singularity,” an infinitely small point containing an infinitely high concentration of matter, expanding in size to what we observe today. The theory of inflation, a super-fast expansion of space proposed in recent decades, fills in many important details, such as why slight lumps in the concentration of matter in the early universe coalesced into large celestial bodies such as galaxies and clusters of galaxies.
But these theories leave major questions unresolved. For example: What started the big bang? What caused inflation to end? What is the source of the mysterious dark energy that is apparently causing the universe to speed up its expansion?
The idea that our universe is entirely contained within a black hole provides answers to these problems and many more. It eliminates the notion of physically impossible singularities in our universe. And it draws upon two central theories in physics.June 3, 2013 at 8:18 pm #7489June 6, 2013 at 11:28 am #7506June 16, 2013 at 4:30 pm #7562
A video map of motions in the nearby universe
An international team of researchers, including University of Hawaii at Manoa astronomer Brent Tully, has mapped the motions of structures of the nearby universe in greater detail than ever before. The maps are presented as a video, which provides a dynamic three-dimensional representation of the universe through the use of rotation, panning, and zooming. The video was announced last week at the conference “Cosmic Flows: Observations and Simulations” in Marseille, France, that honored the career and 70th birthday of Tully.
The Cosmic Flows project has mapped visible and dark matter densities around our Milky Way galaxy up to a distance of 300 million light-years.July 26, 2013 at 11:19 am #7922August 1, 2013 at 10:36 am #8009
A lifetime is too short to understand the amazingness of it all…September 2, 2013 at 11:38 am #8578
I think I’m disappointed…:-(
Loved the ET movie so much…
Silence in the sky…
Dr Armstrong says: ‘There are two ways of looking at our paper. The first is as a study of our future – humanity could at some point colonise the universe. The second relates to potential alien species – by showing the relative ease of crossing between galaxies, it makes the lack of evidence for other intelligent life even more puzzling. This worsens the Fermi paradox.’
Read more at: http://phys.org/news/2013-08-silence-skybut.html#jCpSeptember 6, 2013 at 11:47 am #8619
No one knows for sure, but it is not at all unlikely that the universe is constructed in a very different way than the theories and models of today predict. The most widely used model today cannot explain everything in the universe, and therefore there is a need to explore the parts of nature which the model cannot explain. This research field is called “New Physics,” and it turns our understanding of the universe upside down.September 6, 2013 at 11:50 am #8620
Geophysicists have discovered what they say is the largest single volcano on Earth, a 650-kilometre-wide beast the size of the British Isles lurking beneath the waters of the northwest Pacific Ocean.
The megavolcano has been inactive for some 140 million years. But its very existence will help geophysicists to set limits on how much magma can be stored in Earth’s crust and pour out onto the surface. It also shows that Earth can produce volcanoes on par with Olympus Mons on Mars, which, at 625 kilometres across, was until now the biggest volcano known in the Solar System.January 12, 2014 at 3:05 am #10430
They look like marbles…January 12, 2014 at 3:10 am #10431
The planet marbles remind me of a song from my childhoodJanuary 16, 2014 at 7:15 pm #10516
There’s a quiet revolution underway in theoretical physics. For as long as the discipline has existed, physicists have been reluctant to discuss consciousness, considering it a topic for quacks and charlatans. Indeed, the mere mention of the ‘c’ word could ruin careers.
That’s finally beginning to change thanks to a fundamentally new way of thinking about consciousness that is spreading like wildfire through the theoretical physics community. And while the problem of consciousness is far from being solved, it is finally being formulated mathematically as a set of problems that researchers can understand, explore and discuss.April 6, 2014 at 12:47 pm #11930
In the same spirit…April 6, 2014 at 1:16 pm #11934
We present a comprehensive and consistent meta theory of universes. The Universe is comprised of a long information theoretic bitstring encoding its own grammar and parser that progresses as a big evolution rather than a big bang going through a step function in a recursive fashion. The big evolution posits similar principles identified in biological evolution such as mutation and natural selection, and universes (and portions thereof) may be evaluated in terms of homology and analogy. The big evolution refers to constant dynamic equilibrium of interacting particles (bits of information) contained in a universe as specified by chaos theory . The laws of complexity thus followed the laws of physics.April 15, 2014 at 4:47 pm #12063
Charming brief on de Broglie and waves…”it’s screwy”April 18, 2014 at 2:15 am #12130
“The most exciting phrase to hear in science, the one that heralds new discoveries, is not “Eureka!” but “That’s funny …”
Isaac AsimovApril 19, 2014 at 5:11 am #12146
You gave me great joy by kindly sending me your book “Phantom Walls”, and I hardly need to assert that I will gratefully keep this valuable gift in honour. Not only will it be a cherished souvenir of that eventful and interesting day which I got to spend in London two weeks ago, but by reading it I also promise myself many a new valuable stimulation in addition to the plenty which I have previously received from your writings. – The thing that for me has always made the standpoint represented by you plausible and likeable is your unshakeable faith in the existence of a real outer world independent of us, in which we humans play only a relatively humble and minor role, and your rejection of the positivist viewpoint, which seeks to do away with all questions associated with this real outer world by declaring them meaningless. Rather, we must be content that much will remain mysterious to us, no matter how much we advance in knowledge. But we always have the consolation that we steadily approach the truth, even if we can never fully attain it.April 19, 2014 at 9:54 pm #12168
Alan Guth on other universesApril 24, 2014 at 5:12 pm #12297
Emergent spacetime in quantum theories of gravity
“Although philosophy has acknowledged many implications of relativity, the physics of the past 20 years has started to elaborate revolutionary new accounts of space and time. These are quantum theories of spacetime, or (since gravity is explained by the geometry of spacetime) of “quantum gravity” (QG); string theory is most visible, but competitors exist, especially loop quantum gravity (LQG). These theories are works in progress, but one strong suggestion they make is that space and time are not fundamental ingredients of the world, but somehow arise–or “emerge”–from a deeper reality that does not contain them: much as rainbows, plants or people are “higher-level” phenomena, “effective” entities in physicists’ parlance. This idea that the universe might not, at bottom, be “in” space and time, that these seemingly fundamental ingredients are just the appearances of something more fundamental, would shatter our conception of the universe profoundly. But because the physics is controversial and difficult, despite its critical nature the issue has not yet been investigated in a serious way by philosophers (there are only a handful of papers addressing the issues). However, in the last few years the field has reached a maturity at which such work is possible, indeed urgent;”April 24, 2014 at 5:43 pm #12298
A photon, massless, travelling at the speed of light, experiences no time and no space. Space and time seem to appear when things slow down from light speed. What could limit the speed? Mass? Could mass cause emergence of spacetime? Mass at least warps spacetime, could it also be the cause of it?
What is space, distance, volume then? Something that is forced into existence because things cannot keep up with light? Tension between light and mass? But light is energy, and mass is energy… so is it tension between mass-energy and massless energy?
… must think more…April 24, 2014 at 6:20 pm #12300
I posted this some weeks agoMay 6, 2014 at 9:20 am #12530
“Gnosticism asserts that the world is under the control of the Demiurge and his archons (the Devil and his demons). We live in hell. What could be worse than being ruled by psychopaths who will do anything to serve their own agenda? All right wingers are Satanic. All conservatives, all those who support the dynastic family, inheritance, nepotism, privilege, cronyism and “libertarianism” are psychopaths. You are psychopathic if you are opposed to the rational, meritocratic State. Reason alone is the solution to humanity’s ills. Reason is the antidote to psychopathy.”
“Illuminism contains all of science because science is based on mathematics, but then goes beyond science because science doesn’t even recognize or admit that it is based on mathematics (and it is), and science can’t even explain itself. Science can’t even explain something as simple as where the laws of physics are stored; mathematical idealism can. Science can’t explain free-will; mathematical idealism can. Science can’t explain why something came from nothing; mathematical idealism can. The list just goes on and on. Modern science is actually a faith system even more irrational than Abrahamism.”
“In the Relativity post and in this one the basic justification for the concept of God was given. If you didn’t catch it then it would be helpful to do some reading. Start with the God Series by Hockney, starting with The God Factory.
Keep in mind, as in the quote above, that this is not some childish moronic stupid and absurd faith-based God as in Abrahamism and traditional religion. Not a God you externalize and have to worship or be less-than, etc., not some creator that you have to give thanks to, etc etc. In the simplest terms then, what is evolution capable of producing? Of course the standard materialist answer to that is itself based on faith; the mathematical idealist answer is a complete revaluation, based on logic, not on assumptions or faith.”
Most of the God Series is available for free on the AC website; the books are best read in order of publication date. A mathematical Theory of Everything is explained.
“Absolutely a great book. It explains everything: religion, culture, language. The parts about the anatomy of the brain are probably obsolete due to improved brain scanning equipment today. But Jaynes hypothesis of how civilization and the way we live affect our thinking is enlightening and instructive. He explains how mankind’s consciousness altered with the change from hunting/gathering to agricultural societies. He doesn’t cover it in the book but he lays the groundwork in my mind for how the industrial revolution and large cities have changed us in the nineteenth century and raises speculation on how the information age and globalization is affecting our brains now. Definitely a ground breaking work.”
“Existence is based on monism, not dualism, because there is no sufficient reason why existence should produce an arbitrary number of incompatible substances. If it generated such substances, it would generate an infinite number, not just two. In fact, what existence does is generate infinite instances of one substance. That one substance MUST contain, at least in elementary form, every property that will be exhibited in the universe.”May 6, 2014 at 10:40 am #12532
Hi Gavin and thanks for posting that.
I’m not going to spend much time on the first, other than to say I think it’s nonsense. I think you posted it before.
Jaynes is much more interesting and although I’ve often seen mentioned and read reviews and comments I’ve not read the book. I’m very interested in investigating that whole area, pre-historic consciousness.
The next one looks good too, because if science had followed instead of Descartes and Newton, things might have turned out rather differently. I’ve bookmarked that one to read.May 6, 2014 at 2:44 pm #12539
You’ll have to read the whole series of books, the mathmonism link comes *from* the ToE of the Illuminati and it’s based on intuitive thinking, logic and reason. It all connects up and the mathmonism site is newer, the God Series books are the best of it all. There is for example a criticism of mainstream science which is very interesting.. similarly a psychological profiling of Anonymous.. it’s written exactly for people who think like me, who question everything. I appreciate it is yet more information that could potentially be garbage to you. I’ve had a year to reflect on this.
Yes, funnily enough I know exactly what you mean by “things might have turned out rather differently” through history, because it has been explicitly explained to me in these books. There are many shocks and surprises waiting for the patient reader. I cannot recommend anything more, there’s really nothing like it. From my best judgements this is the sole thing I would recommend to people, for everything. They have thought everything through. They mention Nietzsche, Leibniz, Pythagoras, Plato, Aristotle.. it’s been such a thrilling read.
I will leave it at that.
I got the other unrelated book from here:
Just found a good collection of Russel Brand clips
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