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  1. Let's say the Qualcomm chip cost $30. If the licencing fee is $7.5 per chip that means the chip really cost $37.5. Why does Qualcomm call it a licencing fee? It's simply the price of the chip.

    I think Apple does not have to pay this fee annually or something after they sold the phones to customers.

  2. Physicists believe in negative mass.... on Bizarre 'Dark Fluid' With Negative Mass Could Dominate the Universe (theconversation.com) · · Score: 3, Insightful

    because math allows it. But not everything is real what math allows. Just look at the epic failure of SUSY or read "Lost in Math: How Beauty Leads Physics Astray" from theoretical physicist Sabine Hossenfelder.

    "However, studies have shown that the force driving the accelerating expansion of the universe is relentlessly constant."

    And there are several studies which claim that the accelerating expansion of the Universe is an illusion. I think it would be simpler(?) to explain the galactic rotation problem and/or the Bullet Cluster without dark matter with a model. And if that model also says something about the expansion of the Universe which matches the observations that would be an extra. But no model should be built upon solely on the accelerating expansion of the Universe.

    "It therefore appears that a simple minus sign may solve one of the longest standing problems in physics."

    I have read a study which claimed that the bending of light around a galaxy was consistent with the velocity of the stars around the galaxy. That means space-time is really curved with the right amount since there cannot be any repulsive force which bends light.

    A precise extragalactic test of General Relativity
    http://science.sciencemag.org/...

  3. First, I found QI interesting... on DARPA Is Researching Quantized Inertia, a Theory Many Think Is Pseudoscience (vice.com) · · Score: 5, Interesting

    ...not anymore. The problem with QI is that it is based on Unruh radiation. This Unruh radiation is supposed to replace dark matter and responsible for the peculiar velocities of stars in spiral galaxies.

    Now, here's a problem:
    A precise extragalactic test of General Relativity
    http://science.sciencemag.org/...

    According to this study the rotational velocities of the stars are consistent with the bending of light around the galaxy. That means space-time is curved with the right amount which causes the velocities of the stars.

    So, Unruh radiation cannot be responsible for these velocities since Unruh radiation is light and light cannot "bend" light. Actually, our current understanding is that nothing can "bend" light this way, only space-time curvature. This means there is something there which causes this "extra" space-time curvature (eg. dark matter).

    I do not believe dark matter exists, but it won't be QI which solves these kind of problems.

  4. It will fall down on Physicists Investigate Why Matter and Antimatter Are Not Mirror Images (economist.com) · · Score: 4, Insightful

    This is almost duplicate since I remember a similar article which talked about some experiment by Italian scientists a few years ago.

    But again, our current understanding is that gravity is the curvature of space and time. The anti-matter has no choice but to follow that curvature. It cannot pretend that curvature does not exist.

    So, if anti-matter were actually fallen up you can throw general relativity out of the window. I do not expect that will happen.

  5. 1588 PTP on Google and Nasdaq Pursuing Nano-Second Precision In Network Time Protocol (nytimes.com) · · Score: 4, Informative

    There is already a standard with nanosecond precision (or better).
    It's called 1588 PTP.

    https://en.wikipedia.org/wiki/...

  6. The Orville: Majority Rule
    https://en.wikipedia.org/wiki/...

  7. I just don't understand something... on NTSB Boots Tesla From Investigation Into Fatal Autopilot Crash (theverge.com) · · Score: 3, Insightful

    Shouldn't be the first and foremost use case of an 'autopilot' not to crash into any unmoving object on the road in front of the vehicle?

    If an 'autopilot' cannot do that, it is useless.

  8. Physicists should not be mathematicians, they should be primarily physicists. Not everything is real what math allows. If that were the case, the SU(5)
      model (https://en.wikipedia.org/wiki/Georgi%E2%80%93Glashow_model) would have worked.

    Mathematics can describe reality, but reality is not mathematics.

  9. Explaining the Elongated Shape of Oumuamua on Interstellar Object 'Oumuamua' Appears To Be Wrapped In An Organic Insulation Layer (theguardian.com) · · Score: 5, Interesting

    Explaining the Elongated Shape of Oumuamua by the Eikonal Abrasion Model

    http://iopscience.iop.org/arti...

  10. It may be random to us... on Researchers Build True Random Number Generator From Carbon Nanotubes (ieee.org) · · Score: 2

    but it may not from the Universe' point of view.

    According to Gerard 't Hooft, the superdeterminism loophole cannot be dismissed.

    The Free-Will Postulate in Quantum Mechanics
    https://arxiv.org/abs/quant-ph...

    Entangled quantum states in a local deterministic theory
    https://arxiv.org/abs/0908.340...

  11. Forget time on Physicists Find That As Clocks Get More Precise, Time Gets More Fuzzy (sciencealert.com) · · Score: 4, Insightful

    https://arxiv.org/abs/0903.383...

    Time is just the sequence of events. And events on the smallest scale are particle interactions.

    What if there is an unknown quantum field which creates a barrier between particles? And particles have to "tunnel" through it in order to interact?

    When this quantum field is more disturbed (warped, etc) this barrier will be greater and it would be harder to particles to interact with each other. The end result is "time" slows down since the number of interactions drops.

    Note that an observer (in its own reference frame) will not notice anything (in the same way as in general relativity) since the observer just counts the number of interactions. To that observer the same number of interactions means the same amount of "time" passes.

    And yes, this means this quantum field would be a distinguished reference frame.

  12. They forgot to mention X-Rays on Thrilling Discovery of Seven Earth-Sized Planets Orbiting Nearby Star (theguardian.com) · · Score: 4, Interesting

    Strong XUV irradiation of the Earth-sized exoplanets orbiting the ultracool dwarf TRAPPIST-1

    https://arxiv.org/abs/1605.015...

  13. Isn't this a kind of proof that gravity is push? on Milky Way Is Being Pushed Across the Universe (cnn.com) · · Score: 3, Interesting

    I think space itself is some kind of medium and not necessarily matter based. Currently, its composition is unknown. You can call this medium aether if you like, just do not confuse it with the luminiferous aether. There are several aether theories out there, one of the popular ones is the Superfluid Vacuum Theory.

    Now, back to gravity. We know since Einstein that matter curves/disturbs space**. So, this medium, which is disturbed by matter, wants to be 'smooth' and it exerts a force on matter. This force is obviously a push force and we call it gravity.

    From our perspective there is no way to differentiate between pull or push. Maybe until now.

    ** I know that according to GR gravity is a curvature of space-time and not just space. But if space itself is some kind of medium then the time dimension simply does not exist. What happens is that the disturbance of space prevents matter particles to interact with each other. We perceive this lack of interaction as if 'time' slow down since there is no change (We can only perceive 'time' by observing change). This picture is compatible with GR since relativity between moving bodies through space remains. However, it establishes a distinguished reference frame which is space itself.

  14. Re:Hilarious on China Claims Tests of 'Reactionless' EM Drive Were Successful (popsci.com) · · Score: 1

    Well, they debunked the luminiferous ether, but there are other aether theories out there. A 'popular' one is the Superfluid vacuum theory.

    https://en.wikipedia.org/wiki/...

    Also, Erik Verlinde talks about 'elastic back pressure' in his recent paper https://arxiv.org/pdf/1611.022... concerning 'emergent gravity'.

    Personally I do not think gravity is emergent, but I wonder if elasticity could be applied to space itself. That could explain observations without dark matter.

    Even dark energy can be explained. In this case dark energy would be the elastic energy of space. So, it's no wonder the universe is expanding.

    It has also implications to the fate of the universe. I mean it may not depend on how much matter is in the universe, but rather what kind of properties space has.

  15. Re:Filter or not on ESA: European Mars Lander Crash Caused By 1-Second Glitch (space.com) · · Score: 1

    This is not how Kalman filter works. Even if it gets totally wrong data for one second it outputs "correct" values based on previous data.

    So, in our case the altitude output would have changed for this one second and the output values would have been quite close to the real altitude.

  16. Kalman filter on ESA: European Mars Lander Crash Caused By 1-Second Glitch (space.com) · · Score: 4, Insightful

    https://en.wikipedia.org/wiki/...

    How in hell did they test their Kalman filter to allow such bad data to reach the decision logic? (I assume they used one.)

  17. Space can be elastic on New Theory of Gravity Might Explain Dark Matter (phys.org) · · Score: 3, Informative

    It's strange that Verlinde uses 'elastic' in the abstract.

    "The emergent laws of gravity contain an additional dark gravitational
    force describing the elastic response due to the entropy displacement."

    I think space can be thought of like some kind of elastic material. At first, space begins to regain its original form (where there is no matter) quickly from the center of gravitation. However, as we go further and further from the center this process slows down.

    The end result is that space will be more curved than we expect at large distances.

  18. UBI will be a disaster on Elon Musk Predicts Automation Will Lead To A Universal Basic Income (mashable.com) · · Score: 5, Interesting

    The complete naivete of the slahdot crowd concerning UBI is beyond comprehension.

    It looks like most slahdotters think a simple tinkering with the taxation system (which will mostly affect wealthy corporations and individuals) will bring universal joy to everyone.

    I tell you what. It will absolutely do no good. It looks like everyone thinks that wealthy men keep their wealth in some kind of vault like Smaug. This is not the case. Most of their wealth is already in the economy, there is basically nothing you can get from the wealthy by taxing them more.

    At best UBI will create a society similar to the one in Atlas Shrugged. I do not like to live in such society.

    So, what is the solution to the problems UBI is supposed to cure? Most probably the answer is WAR. Currently, nobody dares to comprehend this possibility.

  19. http://phys.org/news/2011-04-s...

    I think until the majority of scientists do not accept this we won't have a unified theory.

    Even Lee Smolin acknowledges that we have some problem with time (in The Trouble with Physics), but he thinks the problem is that we treat time as a static/frozen thing while he thinks it is a dynamic thing like space itself (eg. the shape of space continuously changes due to matter).

  20. Possible if the Universe is non-local on Can Quantum Entanglement Create Faster-Than-Light Communication? (mit.edu) · · Score: 1

    There are some theories, most prominently the De Broglie-Bohm theory (https://en.wikipedia.org/wiki/De_Broglie%E2%80%93Bohm_theory) which assume that the Universe itself is inherently non-local.

    These theories are basically Aether theories (https://en.wikipedia.org/wiki/Aether_theories) which assume some kind of unknown medium (possible that medium is space itself). Do not confuse these with the Luminiferous aether theory.

    If there is such medium that can explain a lot of things eg. why the Universe appears to be the same in all directions, etc. This was explained before with the Inflation theory, but that one bit the dust (http://www.space.com/28423-cosmic-inflation-signal-space-dust.html).

  21. Financial gain... on Should the US Change Metal Coins? (networkworld.com) · · Score: 1

    And what about the financial gain when they print a $100?

  22. Re:Enigma on Dutch Government Backs Strong Encryption, Condemns Backdoors · · Score: 1

    Obviously, you do not understand how enigma works. With 20 wheels you have an 26^20 initial configuration and defining thousands of wheel turning patters makes the attacker's work much-much harder.

    And actually, cracking the original enigma should takes just a few seconds on today's desktop computers.

    Enigma basically replaces each letter with a different one according to the wheel settings. With 20 wheels the initial configuration contains 20 characters plus the number of the wheel turning pattern. This is far stronger than a simple one-time pad with 20 characters (aka 20*5 bits = 100 bits).

    Also, a wheel can contain the whole ASCII table in which case the initial configuration is 255^20.

  23. Enigma on Dutch Government Backs Strong Encryption, Condemns Backdoors · · Score: 2

    Just create a software version of Enigma (https://en.wikipedia.org/wiki/Enigma_machine) with eg. 20 wheels. Also, create a matrix which contains how the wheels should turn. You can create thousands of wheel turning patters. Voila, unbreakable encryption without using a sufficiently long one time pad.

    Of course, the initial configuration has to be sent somehow (eg. via courier or other conventional ways which 3-letter agencies seem to forget) and the encoding/decoding machine should never be connected to the internet.

  24. No, I invoked the gambler's fallacy because it seemed to me that the original poster assumed that the system has memory.

    It is stated in wikipedia:
    Gambler's fallacy does not apply when the probability of different events is not independent...

    Since I consider different rocket launch as independent events I think gambler's fallacy applies to some extent.

    So, the only way to calculate a success rate of a launch if you get the failure rate of every component of the rocket and do some calculations based on those. However, calculating the success of the 9th mission after the success of the previous 8 or before even the first one has no physical meaning. Maybe it has some kind of theoretical one which has no connection to the physical world.