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Everything posted by MigL

  1. Just to clarify my position, Studiot ... Mathematics treats lines, surfaces, volumes and higher dimensional manifolds as infinitely sub-divisible. Physics, on the other hand, may describe a space-time which is quantized and has a smallest possible value. Now Mathematics will allow you to treat andrepresent those many sub-divisions, no matter how large their number, but if you want to 'count' possible events in a section of sace-time, Physics may have some constraints as to the maximum number of those events.. Perhaps Geordief should indicate which viewpoint he wishes to consider. ( I will excuse your thinking like a Mathematician, if you excuse my thinking like a Physicist 🙂 )
  2. 200 lbs, falling 12 ft, and you catch yourself with your fingertips. 85 times ! you have no concept of reality, or you watch too many movies.
  3. The OP did not deal with 'abstracts', but events in space-time, which are information. The Bekenstein bound does not limit itself to energy/entropy, but applies to all information. Bekenstein derived the 'bound' from entropy considerations of Black Holes, and it was reinterpreted in the framework of QFT by Casini in 2008. Would a 'perfect' shadow be information, or absence of information ? I grant that abstract concepts, such as infinities, can be represented, and Mathematics needs to deal with such 'abstacts', but Physics has constraints; one being the Bekenstein bound.
  4. Life is a struggle against entropy. At its most basic, life strives for 'order' versus the 'disorder' of non-life. IOW, the purpose of life is to not die.
  5. Question asked in the OP The number is finite, so definitely representable.
  6. Getting back to the OP and how much information is required to represent a certain number of events in space-time, Seth has already alluded to an upper limit, here The earth's surface is almost exactly 2x10^84 square Planck units. I vaguely remember reading that something unpleasant happens when you try storing that much information on a limited surface. The Bekenstein bound "implies that the information of a physical system, or the information necessary to perfectly describe that system, must be finite if the region of space and the energy are finite. In computer science this implies that non-finite models such as Turing machines are not realizable as finite devices" See here Bekenstein bound - Wikipedia Sometimes Physicist have to bring Mathematicians back 'down to earth' from their 'flights of fancy'. ( no offence meant, Studiot 😄 )
  7. Institutions, that teach or place, scientists, can , and often do, have biases. The science itself, can not.
  8. Don't wanna nit-pick, but a 'circle-shaped' pie is actually 2 pi. So equating desserts with mathematical quantities is not self-consistent.
  9. You realize that 'oval' is derived from the Latin word for egg ( ovum ) ? ( what a relief; I thought you were asking about your mis-shapen penis )
  10. Really ? They had IQ tests in the 15th century ?
  11. Don't count yur Brexit chickens before they hatch ... The UK MoD through British Aerospace, is developing, along with Italy's Leonardo ( which has a strong presence in the UK with helicopters and electronic systems ) and Mitsubishi of Japan, the 6th generation fighter arcraft, Tempest. BAE Systems Tempest - Wikipedia Rolls Royce is collaborating with ( Fiat ) Avio and IHI to develop hi-electrical output engines to power this 'system of systems'. There is a strong possibility that SAAB of Sweden may also join the 20-25 Billion development program. Doesn't seem like the UK is very isolated to me.
  12. Very bad idea. We don't 'preach' science. We discuss science, and if anyone is willing to engage, ask questions, and learn, we try to answer those questions to the best of our combined abilities. Two things to take away ...| 1 - People have to be willing to engage/ask/learn. 2 - We don't have all the answers, as most of us belong to the previous catagory.
  13. Just like other interpretations of QM superposition of states can be taken to absurd/ridiculous extremes, so can the Many Worlds interpretation. Can a macroscopic cat belonging to Erwin be in a superposition of states, alive and dead, whilst ignoring the multitude of interactions that occurr in a macroscopic object, like a cat, that would cause collapse or decoherence to a singular state. This thread seems to illustrate the point. You can't create mew universes every time an interaction forces decoherence. And H Everett's interpretation is called Many Worlds; Multiverse refers to the Marvel Cinematic Universe.
  14. MigL


    You have a lot of patience Swansont. ( much more than Capiert deserves )
  15. Triggering volcanoes to combat global warming ... That's like cutting off an arm in an effort to lose weight.
  16. Time is included in many models, and has subtle, but nonetheless different aspects. It would be narrow minded to restrict a discussion on the nature of time, to a single, or few aspects, while ignoring the rest. My opnion.
  17. Yes, Seth, time translation symmetry is what accounts for energy conservation locally, but I don't believe that has anything to do with the 'flatness' of space-time. Maybe Markus can do a better job of explaining, but I'll give it a shot ... Generally energy is not conserved in GR as the concept of energy is frame dependent in GR, and what is actually conserved is energy-momentum. Energy conservation would imply a preferred frame, which is not allowed. I'm not sure if Noether's Theorem has a special case for GR, where symmetry in time and position ( in effect, no preferred position in space-time ) leads to energy-momentum conservation. Not sure if this example is valid ( I got it via a google search ), but if the number of photons in the universe is constant, and the universe is expanding and red-shifting those photons to lower energies, then the universe is losing energy ?
  18. It is one way to look at it Seth. But what if the 'energy' isn't just a property of the 'present', and does not have to be consumed to 'construct' the future ? ( GR makes no claims about energy conservation ) What if the 'energy' is a property of the 'block', which includes past, present and future ? Where the present is a ( observer/interaction dependant ) foliation of the block ? Where one end of the block has high useable energy and low entropy ( Big Bang ), while the other end has little or no useable energy and high entropy ( heat death ) ?
  19. Yeah, I sort of knew that. I was trying to make a point; that time is independant, and not related to length. ( as someone did, back on pg 3, I believe )
  20. There are two kinds of measurements. Absolute, as in temperature, where there is a well defined zero point, and all temps are in relation to it, and, gauge, where the measurement depends on where and how the measurement is made; think of a bird on a 15000 v hydro line, that feels zero potential. Time, and distance, are not absolute ( as Studiot has mentioned ), and it makes no sense to say this point is 12 km, or this instant is 17 sec. We specify differences in length with separation, and differences in time with duration. And just like the bird on the wire, we can set the origin of the separation at r=0 and the origin of the duration with t=0 to ease our calculations. Similarly, as INow has mentioned, there is no universal now, or universal present, because there cannot be simultaneity. My 'now' or 'present' differs from the person standing two feet away from me, never mind a galaxy a billion LY away. My now is your future and someone else's past; how do you argue that only the present, or now, exists but past ans future do not ?? And to all those who think that time is simply an effect of motion, that time is emergent from the three spatial dimensions, I challenge you, as Markus did, ( since GR is our map/model of the real terrain ) to find the Panama Canal on a map of Central America from the 1800s. Question for Markus, Mordred and anyone else who may know... We have a separation interval between events as a distance, so we convert the time coordinates by multiplying by c to get a 'distance'. Could we also specify the interval length as a time ( by dividing distances by c ) and would this make any difference whatsoever to GR ? Would some then argue that time is fundamental, and lengths are emergent ?
  21. The 'graviton' would be a massless virtual particle, that is a manifestation of the quantized gravitational field. Off the top of my head, I would think that the distance these virtual particles can 'affect', is determined by the Heisenberg uncertainty principle; massive virtual bosons like the W and Z bosons of the weak interaction can only travel a shrt distance, as they move subluminally and must relinquish their energy/momentum after a certain period of time. The weak interaction, as a result, has a limited range. Gravitons, like photons, would be massless and travel at c , so the 'range' of their interaction could be up to infinity.
  22. If DM was part of the Standard Model we would expect them to be also. So either the SM is wrong and DM has to be included, or, DM was generated in the initial 'genesis' from the hot dense state of the early universe. Either way, wth few interactions to to slow it down, DM moves at relativistic speeds. Why not ? They do have mass, but their high speeds would require extremely large orbits. Depending on the mass of the sterile neutrino, one could calculate the orbital radius and its magnitude compared to galactic radii. You can look up the amount of neutrinos emitted by the Sun each second, multiply that by the number of stars in a typical galaxy, multiply by the amount of galaxies in the visible universe, and multiply by 13 billion years worth of seconds. Does that seem like a small number to you ? So you know what DM particles are ? You seem to 'know' their mass and typical speeds ...
  23. Black Holes were called 'frozen' stars by Soviet Physicists, like Y Zeldovich, simply because the maths describe time running slower, and finally stopping, or 'freezing', at the Event Horizon ( to a far-off observer ). And also because the term 'black hole' has rude connotations in Russian.
  24. What evidence are you basing your conjectures on ? Are you basing this on incorrect assumptions of 'dark' matter and 'dark' energy ? Dark matter is postulated to be of particle nature, and may have anti-dark matter or supersymmetric partners, but dark energy is possibly a scalar field that permeates the expanding universe. x-posted with Swansont
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