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David Albert - What Does Quantum Theory Mean?
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- čas přidán 16. 08. 2024
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Quantum theory may be weird-superposition and entanglement of particles that in our normal world would make no sense-but quantum theory is truly how the microworld works. What does all this weirdness mean? How to go from microworld weirdness to macroworld normalcy? Will we ever make sense out of quantum mechanics?
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David Z Albert, PhD, is Frederick E. Woodbridge Professor of Philosophy and Director of the MA Program in The Philosophical Foundations of Physics at Columbia University in New York.
Watch more videos on quantum theory: shorturl.at/clOTZ
Closer To Truth, hosted by Robert Lawrence Kuhn and directed by Peter Getzels, presents the world’s greatest thinkers exploring humanity’s deepest questions. Discover fundamental issues of existence. Engage new and diverse ways of thinking. Appreciate intense debates. Share your own opinions. Seek your own answers.
Professor Albert makes a great point: if all possible outcomes (regardless of probability) branch out into its own universe, then the likelihood of finding ourselves in any of those outcomes should be the same. Yet, experimentally, we always observe outcomes in proportion to their probability.
For example, if you shoot an electron beam towards a direction, then we always observe them moving towards that direction. Yet if many worlds is correct, we should just as equally likely observe the electrons going in any direction, no matter how low the probability.
The video description asks the following questions:
What does all this weirdness mean? How to go from microworld weirdness to macroworld normalcy? Will we ever make sense out of quantum mechanics?
There is a way to answer these questions collectively using the singlet state for spin-1/2 particles (electrons in this case), thereby showing how quantum entanglement works, i.e., when Alice’s electron is spin down in a particular direction, Bob’s will be spin up in that same direction. This is easy to explain by assuming the electrons were emitted with opposite spins to begin with (like right and left-hand gloves placed into two boxes that are separately opened by Alice and Bob). The real mystery occurs when different measurements are made, because assuming the electrons were emitted with definite values of spin for any direction in space doesn’t match the prediction by quantum mechanics (QM) as verified by experiment (Bell-inequality-violating corrections). There is an easy way to understand why this happens that then answers the above questions. We explain this in our book, "Einstein's Entanglement: Bell Inequalities, Relativity, and the Qubit" Oxford UP (2024), but let me summarize it here.
According to Einstein, special relativity (SR) is a "principle theory," i.e., a theory whose formalism follows from an empirically discovered fact. For SR that empirically discovered fact is the light postulate - everyone measures the same value for the speed of light c, regardless of their uniform relative motions. Since c is a constant of Nature according to Maxwell's electromagnetism, the relativity principle (the laws of physics (to include their constants of Nature) are the same in all inertial reference frames) says it must be the same in all inertial reference frames. And, since inertial reference frames are related by uniform relative motions (boosts), the relativity principle tells us the light postulate must obtain, whence the Lorentz transformations of SR.
Likewise, quantum information theorists have rendered QM a principle theory and its empirically discovered fact is called Information Invariance & Continuity (Brukner & Zeilinger 2009 wording). In more physical terms, Information Invariance & Continuity entails that everyone measures the same value for Planck's constant h, regardless of their relative spatial orientations or locations (let me call that the "Planck postulate"). Since h is a constant of Nature according to Planck's radiation law, the relativity principle says it must be the same in all inertial reference frames. And, since inertial reference frames are related by relative orientations or locations in space (rotations or translations), the relativity principle tells us the Planck postulate must obtain, whence the finite-dimensional Hilbert space of QM.
Quantum superposition is one consequence of the Planck postulate and that leads to 'average-only' conservation, which is responsible for the mystery of quantum entanglement. However, once you understand how ‘average-only’ conservation follows from quantum superposition, which follows from the Planck postulate, which follows from the relativity principle and Planck’s radiation law, there is nothing mysterious about the Bell-inequality-violating correlations of QM. Here is how those correlations make perfect sense using a spin-1/2 example.
Suppose you send a vertical spin up electron to Stern-Gerlach (SG) magnets oriented at 60 deg relative to the vertical. Since spin is a form of angular momentum, classical mechanics says the amount of the vertical +1 angular momentum that you should measure at 60 deg is +1*cos(60) = 1/2 (in units of hbar/2). But, the SG measurement of electron spin constitutes a measurement of h, so everyone has to get the same +/- 1 for a spin measurement in any SG spatial orientation, which means you can't get what you expect from common sense classical mechanics. Instead, QM says the measurement of a vertical spin up electron at 60 deg will produce +1 with a probability of 0.75 and it will produce -1 with a probability of 0.25, so the average is (+1 + 1 + 1 - 1)/4 = 1/2. In other words, QM says you get the common sense classical result on 'average only' because of the observer-independence of h. [Notice that indeterminism follows necessarily, since we have to average the required +/- 1 results.]
Now suppose Alice and Bob are measuring the spin singlet state and Alice obtains +1 vertically and Bob measures his particle at 120 deg relative to Alice. Obviously, if Bob had measured vertically he would have obtained -1, so at 120 deg Alice says he should get 1/2 per our single particle example. But of course, Bob must measure the same value for h that Alice does, so he can't get the fractional value of h Alice says he should (otherwise, Alice would be in a preferred reference frame). Instead, his outcomes at 120 deg corresponding to Alice's +1 outcomes vertically average to 1/2 just like the single particle case. And, of course, the data are symmetric so Bob can partition the results according to *his*
+/- 1 outcomes and show that Alice's results satisfy conservation of spin angular momentum on 'average only'.
In the end, Alice partitions the data per her +/- 1 outcomes and says Bob's results must be averaged to satisfy conservation of spin angular momentum, while Bob's partition says Alice's outcomes must be averaged (Answering Mermin’s challenge with conservation per no preferred reference frame, Scientific Reports volume 10, Article number: 15771 (2020)). This should remind you immediately of an analogous situation in SR. There when Alice and Bob occupy different references frames via relative motion, they partition spacetime events per their own surfaces of simultaneity and show clearly that each other's meter sticks are short and their clocks run slow.
In other words, the mystery of quantum entanglement resides in 'average-only' conservation that results from "no preferred reference frame" (NPRF) giving the observer-independence of h (NPRF + h). And, the mysteries of length contraction and time dilation reside in the relativity of simultaneity that results from "no preferred reference frame" giving the observer-independence of c (NPRF + c).
So, whose meter sticks are really short and whose clocks really run slow? This question arises in the wrong perspective, there is no causal mechanism shortening meter sticks and slowing down clocks in SR. Length contraction and time dilation are not dynamical effects, they are kinematic facts due to the light postulate, as justified by the relativity principle.
Likewise, who has to average their data to conserve spin angular momentum? This question arises in the wrong perspective, there is no non-local or superdeterministic or retro causal mechanism responsible for Bell-inequality-violating correlations of QM. ‘Average-only’ conservation is not a dynamical effect, it’s a kinematic fact due to the Planck postulate, as justified by the relativity principle.
In order to “make sense out of quantum mechanics” the key is to give up the dynamical bias for QM, just as is done for SR.
Every example that Mr Albert mentions before 1:20 makes me believe he has definitely tried a powerful psychedelic before 😂
Dying is safe because consciousness is simultaneous events idiots deem memory.
Quantum theory means that the purpose of Life is Love.
A computer simulation of quantum mechanics needs to make use of a random number generator, which may or may not be stating the obvious. However “fiddling with the equations” is indeed prohibited. When we do a numerical integration of the equations, one remaining possibility is that we make a random choice between a timelike and a spacelike integration. Bell’s Theorem is telling us to start thinking about nonlocal theories anyway.
Awesome love these kinds of videos.
Could it be that single particles have an extreme jitter where we are only able to get a statistical location, and finally only become real when they have coherence with groups of particles? Groups relative to our location.
Subjective experience is an important factor in the many worlds interpretation regarding quantum mechanics.
I’m curious…how so? 👍🏻
@@dr_shrinker because we are perceiving a subjective reality since we had different types of experiences, upbringing, cultures, education, smarts/intelligence, age, etc. which effects the outcomes in space, time, dimensions, and location.
In the 3-worlds framework advocated by Penrose, mathematics, mental, and physical, how does quantum mechanics understand mathematics? I know of set theoretical foundations of mathematics, but never heard of a quantum mechanical theory of mathematics. Regarding the physical world, all we know of it elements seems to be governed by quantum mechanics. Regarding the the mental world, we only know of efforts to explain consciousness using quantum mechanics, as feeble attempts with no discernible possibility of succeeding.
Is there a quantum mechanical theory of mathematics? Can there ever be uncertainty in a world whose inhabitants do not have any degree of freedom since all relations among them is ruled by logic?
When you walk, breath in the double and strength from the leg's sole must happen. This is a typical example of entropy and breath
I'd have a coffee with this guy
CTT introduces me to ideas which otherwise I would likely reject with prejudice. My bad. Thanks for the content and the incisive, informed querying.
The problem with a lot of channels is they stick to one or other party line, while CTT covers a lot of ground, but also a lot of different viewpoints. Many of them I don't find persuasive, but even so Ive come to greatly respect the intellect and integrity of some of the people they interview with view different from mine. I've also found that debating these issues with some of the commenters here has illuminated various ideas I hadn't considered before and has given me an opportunity to sharpen and better reason about some of my own ideas.
@@simonhibbs887agreed
QBism makes way more sense than the many worlds interpretation
With patience comes kindness. Unkindness won't give you the opportunity to be enduring let alone add self-control in one moment
QM classicalized in 2010. Juliana Mortenson website Forgotten Physics uncovers the hidden variables and constants and the bad math of Wien, Schrodinger, Heisenberg, Einstein, Debroglie,Planck, Bohr etc. Further: “The Final Theory: Rethinking Our Scientific Legacy “, Mark McCutcheon for proper physics.
😂😂 Keep dreaming
@@chetanpatil1654 Which and where have you debunked the 158+ pages of the first reference, not to mention ( whoops I just did) the 451+ pages of the second reference? Oh, that’s right you have read neither and are ‘arguing from ignorance.’ Laugh.
Google it to see how it's been debunked.
Noted. Thanks.
books.google.com.au/books/about/The_Final_Theory.html?id=QqxJbHGCP3wC&source=kp_book_description&redir_esc=y
So we are out of matter, which means ..... And we are trained just in one side..... Having stress, internal presurre, fatigue etc.
Can three things be happening at the same time?
I have this nagging feeling that String Theory, Many Worlds etc., are the Phlogiston and Aether of our time. People 100 years from now are going to look back and say to these folks, "What a maroon".
Throw back to Bugs! Love it!
❤😊Love from Italy
The many world explanation (for solving the fine tuning idea of our Universe) might face information and entropy problems.
Wonderful proof of the limitations of the mind as it stands…possibly leading to consider other faculties of the mind or that start on/in the mind to lead to true knowledge…thus an invitation to meditation practice at its origins where what we call in general meditation it has been called dhyana.
I think for the many worlds theory we need to know more about how much energy there is here.. and possibly anywhere. Btw, Pi has a finite value; it is the maximum precision calculable during the lifetime of our universe.
Calculations can have different speeds. That’s like saying infinity is really finite because it depends on the lifetime of the universe.
@@HyzersGRbut it would be finite if the end of the universe meant an end to counting Pi. Even if you calculated Pi instantly, you would stop calculating it eventually. Reaching a thing and maintaining a thing are different. But….you would never reach infinity, even at infinite speed
@@dr_shrinker Pi is infinite and doesn’t depend on the length of length of the universe. A universe of a longer length would still calculate pi for longer than this universe.
@@HyzersGRthat’s if Pi exists in other universes.
@@dr_shrinker the platonic realm is outside of space and time. It doesn’t require a universe to be true
Imagine a photo of a ball in flight. If the ball in the photo is clearly focused, you can know the exact position of the ball, but not the velocity and trajectory. If the photo is blurred, you could know the velocity and trajectory, but not the ball’s precise position. - now apply this to photons, electron, and all fundamental particles we can observe.- measurement problems, wave collapse, and superposition aren’t really about a particle’s speed, it’s about a particle’s vast options for movement, their abundant choices for direction that makes particles probabilistic. Particles aren’t as bogged down as larger objects like molecules, and larger groups of matter that are slave to classical physics.
Always a huge pleasure to see Dr. DaveAlb hard at work educating the planet how to open their eyes and look into the deeper and fundamental questions that are most important to humanity.
I appreciate his charisma, his excellent work in explaining almost a multitude of mathematical, Biological, Cosmological, Philosophical, Quantum Mechanical, TOPICS in a clear , citable (always provides excellent logical and empirical examples and references), and reliable source of knowledge. should I go go on, an expert in the subject matter.
In all honesty we need to take good care of the DR. and allow him to continue his teachings to humanity. When will the world start to GREATLY support these brilliant people to spread this contagious beautiful knowledge that can change the fate of humanity?
If the people with wealth wont support you guys, maybe the MASSES can be converted, and that would be a countless amount of human beings to support and promote their own wealth of knowledge.
Our experience doesn’t account for it, not the other way around
For me the most profound meaning is its confirmation of what newton tells us about his tools of approximation that they are in fact human dashboard equations of the knowledge of good and evil so to speak.
That in fact on scales far from our biases that we can find a sample of infinite degree of Freedom yet uniformity, timelessness without liner direction or anything evil again so to speak, just perfection in everyway.
my dream will be wonderfull thank U so much
👏🏻👏🏻👏🏻☕
I,m everyday looking for light outside... i never see it yet... i know it,s every where... quantum is a joke of old men that don,t understand light great job
maybe a real (energy) mental (quantum probability) multiverse from which decisions can be made?
Five is still single, the tuna is an independent, 0.000000000000000000000001> gram.
Wouldn't it be that other worlds pre-exist and by measurement [observation] "activates" one reality or another?
👏
Its almost always said in hese converstions aboy QM that a particle, an electron for example, can be in two positions at the same time or that there can be two outcomes of its postion measurement. In fact, if we consider an electron shot trough a single hole, it has zillions of possible positions to land on a screen behind the hole, so iit can have zillions of position at the same time. Well, I don't like the expression "can have two, or what ever number (zillion), different positions at the same time" I would rather say that it has different outcomes of position measurements. On the other hand, if we consider interference, we must take into account all the possible paths that a particle can take in order to find the propability distribution of where it will end up when detected. The double slit experiment is usually brought into discussion when the wierdness of QM is discussed, but to me a much more "mysterious" example is light coming into a big telescope: If we think light is composed of individual photons, then every single photon knows how big the telescope's mirror is, how is its secondary mirror supported etc. because only then can the diffraction pattern at the telescope's focus be explained. So in that picture a photon coming into a telescope must go trough all possible paths inside it !
Imagine a spherical uniformly emissive star, the wavefunction of photons emitted from neighboring hydrogen atoms collapsing lightyears apart from each other. Spacetime is weird
the literal opening line suggests a profound misunderstanding of quantum theory. in no way does it suggest 'two contradictory things at the same time' -- if you mean superposition, that is the wavefunction, and generally how waves work.
To be clear, it was Kuhn, not Albert, who spoke the opening line.
@@brothermine2292 lol, regardless quantum superposition is not contradictory in any sense, nor is the WF necessarily in ‘2 states at once’ it’s in a combination of orthogonal states, like spin up or down, but that’s just because we can only measure from one base at a time - it’s just as well in a single quantum state.
@@anywallsocket : I don't think Kuhn meant the _wavefunction_ can be in multiple states. The wavefunction is a description of the state of a system. Kuhn meant that when a system's state is a superposition then the system -- not its wavefunction -- is in multiple states. So Kuhn would say Schrodinger's cat is alive and dead. (Kuhn would NOT say the cat's _wavefunction_ is alive and dead.)
But QM doesn't say the cat is alive and dead. QM says there's a ¹/₂ probability we will observe the cat is alive and a ¹/₂ probability we will observe the cat is dead. To try to go beyond that is to "interpret" QM. (Copenhagen, Many Worlds, DeBroglie-Bohm, etc.)
The alusion is towards wave particle duality.
@@brothermine2292 well technically considering the WF to be mere description is also an interpretation, but regardless there is no difference between the ‘state of the system’ and the WF - for it contains all the state information. When you use examples like the cat, you’re dead and alive states are basis states, but the entangled state is also one state - it’s a bit of a semantic I agree, but I dislike the notion that quantum theory is contradictory.
Quantum physics means you are all have been fooled.
Metaphysician philosopher
The political affiliation of a tuna sandwich. 😂 sounds like Douglas Adams.
Always There Are @ Contradictory Things Happening At the Same Time but mind is Designed By The Ultimate Laws of Almighty to only understand Maximum not more the half at any point of time
Remember, folks: mathematics doesn't exist. It's only utility is mimicing That Which Is, so to better understand her, and most of it is relative and circumscribed to the sensible.
Math doesn't exist in the physical sense. Is that the sense you mean? Some people use the word "exist" in additional ways, and they would say math has an eternal "abstract" (non-physical) existence.
3:18 it explains free will. Action =reaction. One force can be predetermined like sapolsky says - but free will can be kaos or collective free will… quantum theory means - we can do better!
Another opinion; David says: "we have to fiddle with these (QM) equations". I feel that there is another possibility: Lets take the randomness of the measurement outcomes as a basic principle and not try to explain them based on our intuitions that come from our macroscopic experiences. That is: don't try to explain more deep microscopic physics based on emergent macroscopic physics, try in the other direction. :-)
I used to think he was crazy. Later on in life his theories make more sense. Idk.
It probably means we're in a simulation.
No it doesn't
@@onlynormalperson That's exactly what a simulated bot would say. 😆
Sorry, not a sim fan but I couldn't resist it.
*"Sorry, not a sim fan but I couldn't resist it."*
... Yah, but another version of you somewhere out there in the Multiverse _was_ able to resist! 🙂
@@0-by-1_Publishing_LLC 😄
It probably means, this is a perspective you favor personally.
Quantum mechanics says I’m real and in a micro second I do not exist . But a fluctuating ¥ being that quickly would look like both existence do exist in the same reference frame
I applaud Albert's lack of allegiance to the Many Worlds Interpretation ... especially with its lack of adherence to common logic and intuition. The unresolvable baggage attached to the MWI demands that we look in other areas to discover the truth surrounding reality. Accepting that something can simultaneously occupy two distinct areas of space when everything else we observe can't is like learning that 1 + 1 = 2 in kindergarten and then accepting that it doesn't in your PhD dissertation.
Humanity is supposed to *grow* in intelligence as we evolve, ... _not _*_shrink!_*
This has little to do with "What is quantum theory?" It is just another "many worlds" video. This breaks my trust. I don't want to watch this stuff.
Quantum mechanics is undertermist and fundamental Law of phich not show up How to solve unpredictable particles. Guys Quantum mechanics shows predict though probability How figuret out Particles is nil. He model searching Quantum mechanic solutions needs Law of phich proceendings that guys declines It.
...Just listening to Mr. David and yourself my brain exploded in a rush of thought. Time/Space moves as a Turbulent Flow, with Eddie's & Vortices. Thereby you can know many things but you can not predict the outcome because of the Eddie's & Vortices. Also take a step forward, stop and realize there are Infinite possibilities depending on your next step. The Multiverse are Present, right there in front with the very next step, remembering the Time/Space Turbulent Flow with the Eddie's and Vortices effecting that next step. All Every and Every All is before each and everyone of us. Respectfully, Chuck...captivus brevis...Blessings...Please consider the aforementioned carefully. Prior to the Big Bang All Every and Every All existed in an Eternal State. No Past, present, or Future. My you tube is captivus brevis...Blessings in this New Year and new knowledge advanced.
Many worlds and Unicorns, understood by Leprechauns. Some physicists are totally spaced out. A thesis is not a theory or fact. The popular notion is viewed as or rather sold as fact. Get back to reality please.
Quantum = subatomic = no spatial extension
Nope.. EXPECTATION causes quantum collapses even into the perceived past. FAITH runs the kaboodle (true story). Probabilities is the dumbest word ever invented inside our mental universe. CONSCIOUSNESS = SIMULTANEOUS EVENTS = MEMORY (period)
Always good to see a wide open mental universe welcoming a discussion of possibilities. 🤗
@@mandelbot5318 - Expectation is what causes quantum collapses into a "new thought-form"... simplified a new thought.
The standard simulation hypothesis us absurd only in the fact time is not an actual thingermabobber (Official term).
So our experience of linear time is only a perception as odd as that must sound to a BIOLOGIST (chortle/snort/cough).... ze ones who study zee imaginary brain antennae. apparatus.
To "simplify"..
Faith runs the kaboodle.
expectations cause all quantum collapse even into the perceived past.. means the exact same thing.
THERE IS ONE WAY TO PROVE WHAT OI SAY IS TRUTH...
ANALYZE TIMELINES WHEN YOU MANIFEST....
I am not a philosopher. I know the physics of the universe because i am first a teacher of magic.
As odd as that must sound to a person who may think themself "actual".
I belive when rene descartes's mommy told him he was a 'real; boy'.. that is (concurrent to always) a form of child abuse
DO NOT BELIEVE ANYTHING A SAY.. no need...
Energy follows all thoughts.l.which truly you CANNOT miss from now on..
"Think of stuff and pay attention".. not rocket science. Obvious once past the age of seven (7).. I'm intentionally gruff.. don't mind me.
I have "miracles" are too easy" on my channel which is a book that teaches three miracles in the first three sentences.
"Theory of Everything Mind" is also on my channel and is also an audiobook on youtube
I specialize in "dumbing down ' reality.
Once you know EXPECTATIONS transcend time. You would also know why YOUR EGO/SOUL/PERSONALITY...
Your .. consciousness.. is memory.
You are your "building into whatever you are now."
From moment to moment time exists only because we interact with other thought forms and join them in a linear time perception that is simultaneous to forever.
Making you immortal by default.
Materialism is absurd.. bonkers.
Science is completely the dumbest region mankind has come up with. WE cannot ASS/U/ME we are actual from the get go.. that's not very sciency.
Like. how do they know we arent living the dream (we are .. we so are)...
Quantum mechanics has WON.
Space-time (earth air) is a dead dog now.
If you know any academics (chortle/snort/cough) have them google the 2022 Nobel prize in physics to see if it alters their perception on "PHYSICS".
Update they educations.. a 2 hour films
Is professor Jiom Alkhalili (Excellent professor of physics.. and overbudget fun films)
Mind-Blowing Facts About Our Reality [4K] | The Secrets of Quantum Physics | Spark
I can answer any question about the universe... ist all very simple>"
You view every license plate number now.. your mind stores nothing.
Youve never thunk (err thinked) a thought.. your thoughts are more conscious (sentient) than your toaster.
You are resonance.. you are always changing..
GRATITUDE IS A HACK TO LOVE...
REPETION IS A HACK TO FOCUS.
You do not need me to realize truth.
Those who do NOT use magic.. are the fools.
Everything is magic.. look around.
Everything is conscious.
I know how it all works.. that is my claim..
The first consciousness form in our universe was a dot... then a straight line which BIRTHS a third dot.. and OBSERVER.. the trinity.
Every memory that makes you. you are simultaneous to a billion done years form Tommorw.. you can buy tickets to watch it then.
You are human. that's advanced.. your toaster will be a plant to learn to breathe a and a fishy that waggle its buttocks to move.
Now you can breathe and shake yer butt.
and you evolve into your highest self simultaneously to now..
Someone (you) that has walked beside you all the way.. or.. as you.
Is your toaster going to evolve into god?
All hail toaster.
Namaste Wayne
So, David Albert, because you can't measure correctly the natural REALITY, you renounce completely the correct capacities of the human mind, and create phantasmagorical non-real mathematical concepts about reality.
All BS.