Comments by "N Marbletoe" (@nmarbletoe8210) on "Stanford" channel.

  1. For me, one of Dr. Susskind's best and most accessible lectures.  Stanford thanks so much for sharing these!
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  2. +Gary McAllister Everyone who likes youtube cats by extension likes string :?>
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  3. congrats to Stanford tech staff for quality video, sound, and for keeping up with the action.  Thx!!
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  4. 'imaginary mass is a bad thing'  57:25 'it's hard to have a string with one end. unless you're a buddhist... a zen buddhist.' 1:16:15 A string with one endpoint is a point?
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  5. PJ Datayan Hawking as Bran Stark
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  6. rodluvan1976 +Bud E thx 4link!  i think i have it now. the higgs field's mexican hat potential can produce both higgs and ziggs.   the ziggs particle is related to rotation of the field value around the rim of the hat.   the higgs particle is related to radial movement of the field up and down the rim. ziggs is not standard name, but there is no one standard name and there are various modes of the field oscillating around the rim, so there technically would be various particles.   sound right? btw, i like the way he uses 'zilch' -- he explained it though, unlike the 'ziggs.' A unit of zilch is easier to imagine than a unit of weak hypercharge. (how could it be weak if it's hypercharged, lol)
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  7. zarchy55 at each point in real space, there could be that circular motion of the fields... the circles aren't in x,y,z, we couldn't see them circling. i imagine it like another dimension touches space at each point, and that other dimension can oscillate. also what malawigw said is true
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  8. Randomnick123 there's no energy lost. for example, an electron in free flight doesn't slow down like mollasses because of the mechanism. it just bops back and forth from right spin to left spin, coasting along. somehow this flipping gives it inertia, which actually makes it hard to slow the electron down or speed it up. the vacuum acts like some weird slip-n-slide that keeps particles moving at a constant velocity...
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  9. carlninja1 i think Jack is asking if Cesar or Matt or Maria gave an explanation that answered your question. if so it's nice to tell them. then we all know it's all taken care of :)
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  10. 50:20 or so... question: can a right handed electron absorb a ziggs, giving it a zilch of +2? or, can a left emit a ziggs, giving it -1 zilch?
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  11. Spacetime IS actually expanding in between any two objects. It's just too way small to measure between atoms in our body, or between earth and moon.
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  12.  @petegaslondon  haha!
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  13. OneBigPappa haha, WOODn't. I think planting trees is the best way to go -- along with efficiency and renewables. It should never be forgotten, and plant FRUIT TREES so we can eat yeah!
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  14. Anil chauhan an alternating magnetic field would make the electrons flip back and forth repeatedly, for as long as you kept the field turned on. each flip you'd get photons. you'd have a photon factory
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  15. Hjembrent Kent this stuff is so cool.  i'll check out lecture 4...
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  16. Dennis Edlund "could you please name that position" -The point the earth and sun move around is called the barycenter.
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  17. axel detlofsson that's true, but it's an idealization. No lab setup is perfect, so in a real world experiment the electrons would occasionally give off a photon. For one thing, one can't align magnets or anything else perfectly. Stray environmental field could interfere even with the best shielded chamber. I was hoping Lenny would say something to that effect, but he didn't. Nevertheless, when he says the probability is 1, he means mathematically.
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  18. that's engineering. this is physics
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  19.  @jaredgore4818  In any case elastic and plastic are just two types of deformation. A grid may be deformed hyperbolically. That's math, which physics may use if it is useful.
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  20.  @jaredgore4818  Searched "hyperbolic deformation" on google scholar. Returned a few hundred results, such as: "Hyperbolic deformation on quantum lattice hamiltonians" (Ueda and Nishino 2008, J Phys Soc Japan)
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  21. Biology is fine, but people who want to make it political who are barking up the wrong tree
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  22. lol because they ran out of letters in the alphabet
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  23.  @schmetterling4477  Moral of the story: don't put Descartes before the horse.
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  24. why can't they produce a pair? they have enough energy...
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  25. It is just the field value. Just two numbers that a point in space can have.
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  26. Lenny doesn't mention that type of vacuum energy detector, but i thought vacuum energy was measured in the lab as casimir force.
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  27. It took me three years, but I estimated how fast the Sun and Alpha Centauri should be expanding according to the Hubble whachamacallit. It's the speed of a running snail, about 3 mm per hour or so. I had the exact number here a year ago, lemme go find it...
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  28. 1. energy of string proportional to length; as you stretch, new 'string' field gets added. 2. what else acts like that? dark energy. 3. is our U inside a higher D string that is being stretched?
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  29. ***** haha that show was set in albuquerque, and it was pretty accurate
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  30. Heyi Wang they can point to different directions until they flip to match the magnetic field. eventually they'd all flip and be the same. the stronger the field, the sooner they flip.
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  31. i'd give $10 to have him say at 2x, "What's up, Doc?"
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  32. Since the U is expanding and the dark energy density is constant, the total mass/energy content is increasing (unless the U is infinite in size, in which case it's mass/energy is always just infinity)....?
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  33. zarchy55 the field. the Higgs field in this case. it can oscillate at any point in spacetime.
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  34.  @jorriffhdhtrsegg  both. he imagined simple scenarios, postulated simple truths, and then deduced dramatic consequences for theory
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  35. I believe that it he is talking about real values of fields, without complex values. It's not an electric field, just two generic fields, just as an example. The z axis gives the energy of the two fields combined for any combination of their values.
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  36. probably something like pent-up energy
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  37. I thought mathematics can't be derived from logic
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  38.  @xaffimarc  That's what I thought, even though I couldn't hear a thing. "It better not" because if it did we'd probably explode faster than the big bang.
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  39. Randomnick123 right, the vacuum isn't empty. they still call it that, but it can have fields. it does have fields.
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  40. cool story! I did not know they were related.
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  41. if we can count the holes in the Multiverse at least we'll know it's topology
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  42. too many electrolytes
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  43. Jannis Alexakis yes, and if you take a small enough volume it will usually be flat, so they take the limit. thus GR describes local fields, but does not specify the exact large scale shape of the universe...
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  44. The Higgs BOSON doens't give anything mass. The Higgs FIELD gives mass to fermions. This is ordinary mass, like we see around us all the time. There is also mass all around us that is not created by the Higgs field. So it doesn't give EVERYTHING mass, only the fermions.
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  45. 20:00 and on, the term i think is "quark gluon plasma." Lots of research on it now, including a string theory-aided prediction that had some support from experiment. Something to do with the QGP acting as a liquid or gas or something.
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  46. life on earth started 3 or 4 billion years ago.  i think he's saying that the time to evolve intelligence, which is now, 13.8 billion years from the big bang, is coincidentally the same as when the hubble horizon matches the age of the universe.  
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  47. Hjembrent Kent 15:20 is a curious moment in the history of physics lectures.  Like you, I don't see how U expansion relates to evolution.  I think Lenny's saying that someday we'll have to explain 1) why the vacuum energy is what it is, and 2) why the speed of evolution is what it is.  Then we can explain why in our U they are the same order of magnitude... coincidence or some deeper linkage.   Perhaps the answer would come from ability to model the probability distribution of possible universes.  Then we could correlate vacuum energy/ expansion parameter vs speed of evolution for the population of possibilities, and ask if there's a significant relationship. In other words, it's less a metaphysical claim that such a deep link exists, more of saying, "it's an anomaly, and science eventually has to deal with anomalies if we want to expand our knowledge"
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  48. Hjembrent Kent re hubble horizon:  maybe it's the difference between Hubble Horizon and Observable Universe.  the HH is about 15 bly, the OU like 45 bly.   HH:  15 bly  -- light rays emitted now can never get to objects that are now 15 bly away.  . OH:  45 bly  -- light rays emitted by objects 13.5 bya are just getting to us now, from objects that are now 45 bly away (back then, they were closer).   HH:  a future message horizon OH:  a past message horizon (but both are cast in terms of current location of objects) i think i understand it better than i did an hour ago... does it sound right?
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  49. Hjembrent Kent I think I have them straight and that we actually agree on HH vs OU.  The OH is present distance of the furthest object we can see in a telescope, because anything further away today can't have sent light to us, even if it did so at the big bang (really, at the last scattering 380 ky after the bang).  The HH defines the portion of space we can't see by light that is emitted now.   (It's a big thing for me to get my head around, so anything i say is a 'maybe.')     Agree, the HH doesn't change size (as long as the Hubble constant of expansion doesn't change?), but the OU does get bigger over time...  It is curious that both rely on a 'cosmic time' that can define a simultaneous "now" for all things.  I guess the CMB does define a central point in spacetime, the big bang... and it also defines a universal rest frame and clock time.  Pretty amazing, since relativity theoretically got rid of the concept of a universal clock... but then we find one that appears physically, due to cosmology.  
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  50. Eduard Stancu the sun and the earth move around a common center of mass
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  51. Dennis Edlund (embarrassed) ... i guess they do it planet-style? but seriously folks. it's the barycenter.
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  52.  @Enigmaticatious  If the molasses were a superfluid... it kinda works better i think
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  53. Steven676 sure that could happen. i suppose it would be important if the experiment were using a weak field and wasn't shielded from the earth's field.
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  54. Frank Sang yes, and how about a negative footprint!
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  55. it does
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  56. it's a funny determinism though, like many worlds is said to be deterministic. we need a better word for it, like meta-deterministic, since the determinism is in principle not accessible to an observer inside the universe.
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  57.  @david203  oh i know they are very different! But considering determinism... Can Bohm predict the timing of a decay of a particular atom of Tungsten 180 held in a vault in Zurich?
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  58.  @david203  MW is not deterministic, although it is common to read that it is. Carroll argues that Many Worlds is standard quantum mechanics. I agree, for now. QM is not a deterministic theory, although Carroll himself might say it is. The wave function progresses in a deterministic manner, but what is the wave function? It gives you probabilities! Perhaps there's different levels of determinism, hence the disagreement with some pretty obvious arguments on both sides.
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  59. If I recall, zilch = weak hypercharge
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  60. blue and red move the same speed. they are different frequency
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  61. he didn't say either of those things.
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  62.  @annettebertora4434  I'm not saying nutthen. I didn't see anything. I never met them. I didn't do it! That's my story and I'm sticking to it.
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  63.  @annettebertora4434  Cats are people too. They are just meowsunderstood. . Susskind is talking there about an imaginary box not a proton. . Later he says The proton mass comes mostly from the kinetic energy of quarks and gluons rattling around in a box. . But it's not the same box,
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  64. or is it like a coin, only two sides?
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  65. but you matter
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  66. you're using it
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  67. all particles actually have some mass because they all have some energy, and E=mc2. the term "massless particle" is common but should be "rest-mass-less particle" to be correct.
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  68. the higgs field is a field with a mexican hat potential it has two oscillations, naturally one gives mass to fermions the other basically just shows us the field is there, and has the predicted properties
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  69.  @dustin741  Yes this is the principle on which a rice cooker works. When the water has become all vapor, the heat rises rapidly and the cooker turns off.
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  70. life as we know it would be impossible without a supply of infinite uncertainty
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  71. the amount of energy is not intrinsic to the photon, it is relational
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  72. for example, the same photon could be viewed with different frequencies by different observers depending on their relative motion
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  73. The Higgs field is the condensate, basically.   The Higgs field can oscillate in two ways. One type of oscillation gives particles that trade zilch with electrons, giving them mass. Another type of oscillation is the Higgs Boson, which doesn't give things mass, but is cool because it shows they got the whole idea right.
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  74. the whole wall is the observer, minus the slits? then the detector is the next observer for the ones that didn't hit the wall...
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  75. I think the professor started early lol man i love this guy
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  76. Why does the Born rule lose info? I can't predict the outcome, so I have no information about the outcome. Then the "cosmic dice" roll and I gain information.
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  77.  @davidhand9721  Fascinating thanks! That will take some time to upload to the microtubles.
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  78. he often omits mere numbers, he's a big picture guy
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  79. The Higgs boson just shows that the Higgs field exists. It is a different oscillation of the field than the oscillation that involves mass. It is a circular oscillation, while the mass thingy is a transverse oscillation. If I recall correctly.
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  80. that happens if you ignore peculiar motion
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  81.  @shellydas1416  they are closely related right?
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  82. yes
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  83. The math of special relativity says that anything moving at c cannot experience internal changes. It's a stopped clock. Flipping is like a clock ticking.
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  84. i think it's an imaginary ruler that is glued to spacetime so it expands with it
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  85. because it's not mollasses
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  86. no
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  87. better call Saul Perlmutter
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  88. they don't assume that
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  89.  @STONECOLDET944  Ok I can see what you mean. The standard model assumes a spacetime background that exists independent of the fields. What I meant was, physicists know the standard model is not complete, so this assumption is the subject of much research, as you point out in terms of quantum gravity.
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  90. yes, only because it has more energy
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  91.  @Overwriter  thanks cool explanation of dx
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  92. yes, and that distance is the radius of the 'cosmological horizon'
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  93. c squared is known, why solve for it?
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  94.  @fnln2536  yes I will go with that, anything with mass is a clock! But how does that make time an aspect of space? Why not space is an aspect of time? Or, they are two different aspects of spacetime, the background void of existence?
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  95. I would assume yes, both types of mass would disappear. But they would still have mass-energy.
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  96. 1. a clock can be attached to any object such as a planet. the clock then reads the proper time for that planet. 2. movement is relative. there is no distinction between moving and not moving objects in a fundamental sense.
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  97. it produced pairs
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  98. I wonder if that is a myth.
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  99. they would be massless in the standard model IF there were no Higgs field.
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  100. The Higgs Boson is a fart from the turtle that gives mass to fermions.   Without massive fermions no structure would be possible.   Without structure the universe might exist but nobody could know it.   If it can't be known, does it really exist?
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  101. it is just a number that doesn't mean anything except, the value of the field at that point in spacetime. knowing the value of the field, we can use the mexican hat potential to know the energy that that point contains due to the Higgs field
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  102. The Higgs field is a field, a state of spacetime. The Higgs boson is one particle that is due to the field.
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  103.  @musikinspace  yup! everything has a wavelength
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  104. It is sometimes an input that is unknowable in principle a priori. Such is life, are we to complain? This is life as a creature smaller than the universe.
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  105. actual and apparent are the same thing, if all we know is what we can measure or observe. more useful terms could be "invariant" and "relative"
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  106. the wave is a probability wave kinda thing, it's not like a water wave that is massive and energetic.
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  107. mass distorts spacetime. this is a theory with a great deal of confirmation and no evidence to the contrary, yet.
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  108. every point is a center
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  109. because try, it does not
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  110. yes it is huge. the planck mass is about a dust grain
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  111. maybe if we collide two dollars together fast enough...
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  112. Basically, if you add energy to a particle it increases it's total mass (by E=mc2). A magnet has more energy in one orientation than the other, if there's a magnetic field. So the magnetic field makes the magnet have more or less mass, depending on it's orientation.
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  113. What you call fudge is the caramel of investigation, the Hypothesis. EM theory would also have such sugary treats. I assume it has some proposals? What is one proposal of EM theory?
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  114. How could it be un-uniform?
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  115.  @hasanshirazi9535  oh yes, thank you! Perhaps he meant if two 0.511 photons collide they could produce a pair...
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  116.  @hasanshirazi9535  Usually... but if the energy is high enough they can merge to produce a pair At least that's what I read, it's not like I make pairs for breakfast.
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  117.  @hasanshirazi9535  Apparently it was not actually observed until 2016... https://cerncourier.com/a/atlas-spots-light-by-light-scattering/
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  118. it means that creating the Higgs boson took a lot of energy, so it was hard to do. it also means there aren't many if these bosons zooming around spacetime. the field is everywhere but the boson is rare
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  119. belief is said to be subjective and science objective. but, how to define objective? maybe it's basicaly the sum of all subjective views
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  120. the category "human" is too limiting perhaps.
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  121. basically it shows that the Higgs field exists. And the field gives mass.
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  122. One orientation has more energy than the other. By E=mc2, this means it is also more massive.
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