Why The Quantum State Only Exists In Our Mind
Dr. David Schmid, Dr. Lídia Del Rio and Hans Busstra explore a metaphysical shift that’s happening in the foundations of physics: the wave function is no longer regarded as something real, but just as a description of what we know about the world. In philosophical terms: the wave function is not ontic, but epistemic. And in more popular terms: the multiverse is science fiction, resting on a too-literal interpretation of a piece of mathematics called the Schrödinger equation.
Our previous video with Dr. Del Rio on the Frauchiger-Renner thought experiment:
https://www.youtube.com/watch?v=v7kxWT_zI60
Three other ‘epistemicists’, who’ve just been awarded a prestigious prize in the foundations of physics:
https://www.youtube.com/watch?v=NnAj66Z1kNQ
Chapters marks
00:00:00 Introduction
00:03:30 — When did it dawn on you that QM is weird?
00:05:54 — The quantum phenomena that still scare David
00:07:53 — How to account for non-locality
00:12:19 — “What are the symbols representing?”
00:15:34 — What is the wavefunction really?
00:17:00 — “The standard view we are taught in the classroom…”
00:19:23 — Classically explaining quantum
00:20:23 — On Wheeler’s delayed choice experiment
00:28:38 — How to interpret the delayed choice experiment
00:32:56 — How can a single particle ‘know’ what’s going on at both paths?
00:36:41 — Quantum phenomena that remain weird: contextuality
00:44:38 — What are the viable ontological explanations we have?
00:48:26 — Is there evidence for an epistemic interpretation?
00:52:56 — Understanding epistemic interpretations
00:57:28 — Are we in a new era of physics?
01:00:43 — Lídia on what constitutes measurement
01:04:36 — How relevant are these recent theoretical findings?
01:07:36 — Experiments with AI as an observer?
01:08:36 — David and Lídia on what consciousness is
01:13:51 — Closing thoughts
Links to relevant scientific work of Schmid and Del Rio:
Why interference phenomena do not capture the essence of quantum theory
L Catani, M Leifer, D Schmid, RW Spekkens
Quantum 7, 1119
A review and analysis of six extended Wigner’s friend arguments
D Schmid, Y Yīng, M Leifer
arXiv preprint arXiv:2308.16220
Guiding our interpretation of quantum theory by principles of causation and inference
D Schmid, Thesis, University of Waterloo
https://uwspace.uwaterloo.ca/items/7aed8173-684a-40af-bff5-e625f29fe810
Thought experiments in a quantum computer,
Nuriya Nurgalieva, Simon Mathis, Lídia del Rio, Renato Renner:
https://arxiv.org/abs/2209.06236
All music licensed under Storyblocks and Soundstripe
Stock footage licensed under Storyblocks
Images from ‘Oppenheimer’ under fair use policy.
Interview content copyright by Essentia Foundation, 2025
www.essentiafoundation.org
@hankchinaski_
August 12, 2025 at 6:47 am
pony tails…… PONY TAILS…. forget about quantum blahblahblah…. PONY TAILS….. smfh
@DerrickMapps
August 12, 2025 at 6:47 am
Lydia has so much going on her mind it seems like she is going to explode. So intelligent
@EarthboundJenna
August 12, 2025 at 6:47 am
I think it's long overdue that Physics and Philosophy just get in a room and kiss already lol
@EarthboundJenna
August 12, 2025 at 6:47 am
Y'all need "Anekantavada" 😘
@boom1538
August 12, 2025 at 6:47 am
Serious mental issues on that david guy…
@verschuiving
August 12, 2025 at 6:47 am
Thank you for this conversation. As a ‘non-fysicist’, but full of curiosity about essence en restoring feedbackloops in our communication and renewal of our broken systems, I would love you to give a summary of quantum fenomena. It would be so helpful. I reckognize the situation that we think of quantum as weird and it is like a spell that went on for several decades now. We need to reverse the hypnotic trance we are in. Teilhard de Chardin, Stephen Wolinsky, Frederico Faggin and Carl Jung helped me to understand that we are in transition to deeper understanding of mankind and have better lives once we understand quantum reality. Jung says in his book that our individuation (knowing oneself) is under pressure. Quantum stuff is a big part of understanding consciousness better. Your podcast is very helpful ❤️❤️❤️
@timmyturner7494
August 12, 2025 at 6:47 am
There’s something really distracting here.
@MengfeiWang-jk4gf
August 12, 2025 at 6:47 am
Also in our envision, our imagination, our emotion.
@LyzStarwalker
August 12, 2025 at 6:47 am
What’s the deal with the lollipop hairdo? lol can’t take him seriously looking at his face.
@p0indexter624
August 12, 2025 at 6:47 am
the intellect of a person not withstanding,
there is a threshold that one exceeds regarding the tolerance of certain idiosyncrasies.
just saying.
@pdoerr742
August 12, 2025 at 6:47 am
Regarding the double slit experiment conversation around 18 minutes. Could it be in the example where there is a detector on the slit where the photon doesnt go, it still knows it there – could it be that the interference from the detector caused enough action to "remove" that path out of the infinite paths it executed before collapsing to the least action path we usually see. Like he said, seems there is an observer aspect to this, could the phase shifter cause enough action to make it not the least action path (least action path is what becomes out reality)
@souravdas5837
August 12, 2025 at 6:47 am
Lidya will you marry me
@viralsheddingzombie5324
August 12, 2025 at 6:47 am
The MWI is not and cannot be viable.
@AmigosdeEster1
August 12, 2025 at 6:47 am
– Has this been confirmed experimentally?
– Yes.
5 seconds of silence, staring intently at each other 😂😂😂
@bestof1506
August 12, 2025 at 6:47 am
It's such a shame that Dr. David Schmid's vocal fry is so grating to my ears, I really want to watch this video but I have to stop because I get overwhelmed.
@RKPT9
August 12, 2025 at 6:47 am
It is the mathematician's religious state of mind.
@CorpseOfSisyphus
August 12, 2025 at 6:47 am
Excuse my ignorance and complete lack of knowledge on any of these topics, but when describing the paradox with the double slit experiment and the "virtual" vs actual essentially exchanging information or outcomes… something you said earlier got me thinking and to be fair, I'm not going to be able to articulate my thoughts or foresee any technical oversights in my question. But… the idea that the absence of the particles presence in the other slit could still yield information to effect the results lead to me imagining a room filled with water. In the center of that room is a wall similar to the double slit experiment and two holes. If you send anything through say the right hole, wouldn't the medium in which the thing is traveling through still effect the other hole? Since this example is a liquid, if I force even the water through the right hole, wouldn't the distribution of the medium itself make its way through the left hole "backwards" into the initial chamber to equalize the difference? Again, I have zero knowledge and to even claim a laymen take on these things feels like I'm overstating. But could there be something akin to this even if not a 1 to 1 parallel to idea, but some kind of weird function that happens similar to it?
I wish I could think on these interesting topics more clearly and with more of an education and knowledge rather than poke at it through the lens of sheer ignorance. But if anyone is willing to offer some sort of eli5 explanation on what I'm trying to say I'd appreciate it. Thank you! Also thanks for the video.
I'm only halfway through and I was at work when I was listening so tbf he will/may have addressed it and I missed it.
@Frank-lf3gf
August 12, 2025 at 6:47 am
Wave function is every possible outcome, but to assume it all plays out that the collapse is the one we're in I think is pappostrus.
@Davysguru
August 12, 2025 at 6:47 am
Everything is one.
@Carlos-kt1wo
August 12, 2025 at 6:47 am
If quantum physicists had discovered die then the world would be weird indeed…
Dice would have different quantum states which would collapse upon observation but when unobserved they wouldn’t be in any one quantum state…
However, the equivalent of the double slit experiment would be weird indeed – if you observe one single die, each number would have 6 states and each would have the same probability, but watching 2 dice would create an “interference” pattern with 36 states but with different probabilities!
@KosalYan-f1c
August 12, 2025 at 6:47 am
❤ with respect, if quantum computation only exists in the mind. Now_"the question is, why you guys can't find the answer to the Big Bang question who made us and why are we here on earth????."
@Gandalf98
August 12, 2025 at 6:47 am
The vacuum carries information…but how fast? If our interferometer is on a scale of the solar system or even galaxies, how can the vacuum carry information of a beam splitter if that beam splitter is placed billions of miles away from another possible path of a given quantum?
@jgilldrafting
August 12, 2025 at 6:47 am
What's the point of the slits when you're sending one particle at a time?
@James-ll3jb
August 12, 2025 at 6:47 am
Equations are but artificial quantity juggling. They are NOT 'reality' and actually are flat ratiocinations of interpretations of appearances.😅
See "Intuitionism" and the philosophy of mathematics of Wittgenstein.
@garysantos7053
August 12, 2025 at 6:47 am
It’s more like, why is the linear mind (the Measured Rational Mind) absent from the “Infinite Quantum State”
@Q.f-bit理論定義者
August 12, 2025 at 6:47 am
This whole shift from ontic to epistemic interpretation fits perfectly with what I’ve formalized in the f-bit theory.
Instead of treating the wavefunction as a “thing,” I define reality as a resonant frequency differential — Δf — between possible states.
The equation:
f-bit = Δf × I
shows that information isn’t stored in objects, but emerges through interference and resonance.
The quantum state isn’t in the world — it is the difference we experience through intentional resonance.
— f-bit Originator (Japan)
@hanaanrosenthal
August 12, 2025 at 6:47 am
There is no evidence that the universe IS physical. None. We just know we experience it and most people are extremely uncomfortable with not actually existing.
@charlesrosenbury231
August 12, 2025 at 6:47 am
I find the concept of psi-epistemic compelling. I have thought this for a long time. The novelty in this description is the claim that the vacuum is communicating information.
Some might argue that this is the realm of God and religion, while others might argue a dimension for which we have no evidence.
We certainly accept that vacuum is not "nothing" but we have no evidence that anything exists there except fields. Which begs the question of whether the assertion solves any problems.
Except possibly the quantization of gravity.
@shadiefox1
August 12, 2025 at 6:47 am
I'm not contesting, just solidifying..
@shadiefox1
August 12, 2025 at 6:47 am
K. By your logic, basic physics goes up in a puff of imagination, as well…?
Comments are closed.