Sean Carroll on Causality and the Arrow of Time

Sean Carroll speaking at the 6th International FQXi Conference, "Mind Matters: Intelligence and Agency in the Physical World."

The Foundational Questions Institute (FQXi) catalyzes, supports, and disseminates research on questions at the foundations of physics and cosmology, particularly new frontiers and innovative ideas integral to a deep understanding of reality but unlikely to be supported by conventional funding sources.

[aliciaphillips]

How does this not have more likes? I just don’t understand the world these days. Thank you for the information. I truly appreciate it.

[briancannard]

The best use of the Fund's money! Thanks Sean! I think in the world, very many engineers and scientists who were thinking a very long time about entropy and information, come to very similar conclusions. I wonder how will it play out. Also recommend to check Susanne Still for a great deal of overlap between causality and computation. Thanks Max for starting all of this! <3

[davejacob]

the most important part, at the end, where he is actually saying why causality suddenly needs a direction (which i think is highly implausible as a conclusion, given everything he said before, why even try to get to this conclusion? zero need for it, just go with "we can talk about causality both ways, but given how our knowledge of past and future differ, we do not have much need for talking about how the future causes the past") was pretty unclear to me. at that point, it seemed like ONLY purely mathematical stuff, nothing i could get a grip on.

[rainerwahnsinn]

2:04 slight correction “number of different microstates corresponding to *same* macrostate”

[cmdr.shepard]

1:05 Because cats are known for their grudge and they still hold one for Schrödinger's.

[samcollins]

Infinity seems to have an affinity to be more infinite.

[eel]

watching in 144p thought that egg was a galaxy 3:32

[cripmeister]

There are more words in this 21 min video than in a typical Stephen King book

[vgzvusr]

14:56 Meanwhile, actual life goes on parallel to the calculator deciding the right equation.

[sadovniksocratus]

Cause and effect is omnipresent in our everyday lives, as well as in quantum mechanics.
And if in modern philosophy this concept (cause and effect) causes controversy,
then this is due to a misunderstanding of the essence of quantum mechanics.
----
''If you are not completely confused by quantum mechanics, you do not understand it''
/ John Wheeler /
''Quantum mechanics makes absolutely no sense'' /Roger Penrose/
"Nobody understands quantum mechanics and that's a problem". /Sean Carroll/

[zzscotty]

At the end of 2001, a very old Keir Dullea knocks a glass of wine over.

[bxoit]

Is it possible to imagine, consistent with the known basic Laws O' Physics (TM), but ignoring the kaon, an hypothetical cosmos containing two regions where the arrow of time, and the entropy gradient through time, is reversed, the one region compared to the other, with, in each of the regions, information-processing entities that can remember the past and decide what to do in the future? When I say "future", I mean in the direction of increasing entropy in that region.

Can we, whose origin is the Big Bang and whose fate is the heat death, construct a time-reversed "and" gate?

Can we, whose origin is the Big Bang and whose fate is the heat death, construct a temporary arrangement in a confined space, where the arrow of time is reversed?

Suppose we build a spherical shell and suspend in the middle of it, on a stalk, a little ball. The stalk contains refrigerant lines or thermocouple wires so that by using an apparatus external to the spherical shell, we can refrigerate the little ball that is in the middle. Suppose we do that, and we also heat the outer shell. Inside the shell, the shell will radiate inward due to its blackbody radiation. The little ball in the middle will absorb this energy. Again, inward radiation. This is the opposite of the circumstance of humanity, where we live near a hot ball that is radiating outward to the relative coolness of the CMB. Does the apparatus I described create a local and temporary region where the arrow of time is reversed?

[artstrology]

The reason the wine glass spilled, is because the previous 3 glasses did not. I have tested this to ad nauseam.

[thomaslwilson]

The laws of physics work in the present, but do these actually work at 13.6 billion years ago? We know about 5% of the mass of the universe, but not about dark matter and dark energy. Clearly we are missing something! But what?

[DavidporthouseCoUk]

You appear to have decided that the Universe is deterministic. Do you think that a computer simulation of quantum mechanics might have any use for a random number generator? Access to an RNG gives us access to the Vernam Cipher which may be useful in dealing with spooky action at a distance. There could be a lot hanging on your answer.

Personally I think a computer simulation should be modelling tachyonic Brownian motion for objects much lighter than the Planck mass, which means a random choice between a spacelike and timelike numerical integration. It should model classical Brownian motion for heavier objects like observers, which is merely decoherence in other language. My RNG will be kept busy.

[frankdimeglio]

Time DILATION proves that ELECTROMAGNETISM/ENERGY IS GRAVITY.

By Frank DiMeglio

[vgzvusr]

4:50 Physists making the case for AI. Certainly, human could not have no information at all, unless we're talking about an AI with a manipulable memory.

[raybeeze]

I don't think you got abrogated right.

[frankdimeglio]

Mr. Shashi Singh (an excellent instructor of physics who is honest) has given the below writing the thumbs up. Moreover, he wrote: "Awesome !" and "Absolutely right."

Excellent !!!
It's all clearly correct.

THE TRULY SUPERIOR UNDERSTANDING OF PHYSICS/PHYSICAL EXPERIENCE:

E=mc2 is DIRECTLY AND FUNDAMENTALLY DERIVED from F=ma. Carefully consider what is THE SUN. The Sun is E=mc2. The Sun is ALSO F=ma. This explains the PERPETUAL MOTION of the Sun, AS gravity/acceleration involves BALANCED inertia/INERTIAL RESISTANCE; AS ELECTROMAGNETISM/ENERGY IS GRAVITY. GREAT !!! ACCORDINGLY, GRAVITATIONAL force/ENERGY IS proportional to (or BALANCED with/as) inertia/INERTIAL RESISTANCE; AS ELECTROMAGNETISM/ENERGY IS GRAVITY. (Very importantly, outer "space" involves full inertia; AND it is fully invisible AND black.) ALL of SPACE is NECESSARILY electromagnetic/gravitational (IN BALANCE), AS ELECTROMAGNETISM/ENERGY IS GRAVITY. This is, IN FACT, proven by F=ma AND E=mc2. (BALANCE AND completeness go hand in hand.) So, consider what is c (A POINT, A PHOTON). A PHOTON may be placed at the center of THE SUN (as A POINT, of course), as the reduction of SPACE is offset by (or BALANCED with) the SPEED OF LIGHT; AS ELECTROMAGNETISM/ENERGY IS GRAVITY. Gravity IS ELECTROMAGNETISM/ENERGY.

The BALANCE of being AND EXPERIENCE is essential. Dreams balance being AND EXPERIENCE. In dreams, it is you AND other than you are IN BALANCE. Indeed, there is no outsmarting the GENIUS of dreams. Dream experience is/involves true/real QUANTUM GRAVITY. MOST IMPORTANTLY, in dreams, BODILY/VISUAL EXPERIENCE is invisible AND VISIBLE IN BALANCE. (THE EYE IS THE BODY.) Dreams make thought MORE LIKE sensory experience in general, thereby improving upon memory AND UNDERSTANDING. INDEED, the ability of THOUGHT to DESCRIBE OR RECONFIGURE sensory experience is ULTIMATELY dependent upon the extent to which THOUGHT IS SIMILAR TO sensory experience. MOREOVER, it is ALSO a very great truth that THE SELF represents, FORMS, and experiences a COMPREHENSIVE approximation of experience in general by combining conscious and unconscious experience. (THOUGHTS ARE INVISIBLE.) Dream experience is possible/potential AND actual IN BALANCE. BALANCE AND completeness go hand in hand. Dream experience is always that of what is the BALANCED MIDDLE DISTANCE in/of SPACE. GREAT. Dreams combine, BALANCE, and include opposites.

By Frank DiMeglio

[pjeffries]

OK, so I'll watch these when people admit time is a concept, not something we sense.