What If Physics IS NOT Describing Reality?

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Neils Bohr said, “It is wrong to think that the task of physics is to find out how Nature is. Physics concerns what we can say about Nature.” Well it turns out that if we pay attention to this subtle difference, some of the most mysterious aspects of nature make a lot more sense.

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Hosted by Matt O'Dowd
Written by Matt O'Dowd
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[LittleSoterios]

Heisenberg also wrote "what we observe is not nature in itself but nature exposed to our method of questioning".

[tensevo]

This is the kind of physics I understand. It makes sense that physics is a model of our perception of the world, and not the world itself. The map is not the territory.

[tekrunner]

As a programmer, this was the most intuitively understandable episode in 7 years of PBS Spacetime.

[synapse]

A fundamental thinking error i think is the idea that an "observer" must be a being. In my understanding an observation is made in the same way any other interactions or measurements are made and that qualifes even light from the sun interacting with the moon's surface as an observation, therefore it exists even when no person or entity is looking.

[anywallsocket]

This is exactly what the philosophy of science is actually very important: those who study epistemology to any degree are already familiar with our limits, yet those only familiar with science perpetually conflate the map for the territory and are surprised when it’s information that constitutes our models for reality — even suggesting the universe is a simulation, because they literally forget we are doing the simulating, and the information is the only thing we CAN understand.

Truth is so close to our noses we forget to notice, let alone discuss its nuance.

[sameddington]

This is one of the most lucid, lens-expanding descriptions of this that I've ever seen. Thanks for this, Dr. O'Dowd!

[moguls]

I love PBS Space Time so much - it is one of the few channels that I have to re-watch portions of the video more than once, and watch the whole video a couple times over with some time in between to digest all the information

[jaggonjaggon]

Everyone is always asking: "What is physics?"
No one is ever asking: "How is physics doing?"

[adamjbond]

These videos, along with those by David Butler, Fermilab, and Arvin Ash, have taught me more about physics than I ever learned in school. They are so much better at transferring knowledge and making physics fun!

[cozymonk]

I've been saying for years that physics and math aren't the laws that govern our reality, but languages we create to describe our understanding of them, whenever the subject comes up. Thanks for making me feel smart!

[eafortson]

This episode was such a pay off for those of us who have been on this journey of discovery with space time from the beginning. It feels like season finale of the 8th season of a show where it basically explains that everything you thought was important was actually meaningless, and that the acceptance of this fact is actually the point.

[Nomen_Latinum]

What this all suggests to me is that the physical reality behind quantum mechanics is explicitly non-local (e.g. Bohmian mechanics), and it is the process of gathering information about a system that imposes locality. That is, gathering information is an inherently local process.

[pabloagsutinnavavieyra]

I really appreciate this humble view on how physics try to model just our observations of reality and try to see if according to our models, we can make further predictions. Sometimes they are right. But interestingly, the gap created when they don't, is where the scientific model can bring something new to the table. So you start merging observations with rigor and creativity to find better explanations, and thus, better models. It's very fun!

[patrickdaly]

Okay, but there really was a pygmy mammoth, called the Channel Islands Mammoth. It's actually one of the most used examples of Insular Dwarfism

[caty]

_"What we model is not the reality but our experience of reality."_
that's very deep!

[muthukumaranl]

I am with Einstein here, the informational interpretation of reality while compelling, still points to the same thing that the traditional interpretation hints at, which is that our understanding of reality is not complete given the units of information we can see/understand (not literally with our senses alone here, but scientifically) & therefore the knowledge we build around it. It does not describe anything about 'fundamental reality' but merely points us to the idea that our traditional descriptions of reality are limited to the underlying informational limitations that we currently have & therefore that we only currently describe our understanding of the reality (informationally) & not reality itself...

[mickomoo]

Love that this channel not just teaches physics but contextualizes it with good philosophy of science.

[thorstenwestheiderphotogra]

Can't help but quote Douglas Adams: "There is a theory which states that if ever anyone discovers exactly what the Universe is for and why it is here, it will instantly disappear and be replaced by something even more bizarre and inexplicable.

There is another theory which states that this has already happened.”

[kanib.]

I was literally just describing this concept to a friend of mine and he introduced me to you. I look forward to watching!

[mrqs]

sending the electron through a magnetic field doesn't seem like asking "are you spin up or down", but rather "will you orient yourself up or down when subjected to this field" - and it seems logical that the left-right alignment would be random after that since then you're asking "will you orient yourself left of right when subjected to this orthogonal field".

anyway, taking this sort of observer centric view probably often leads one to boltzmann brains and other rather useless hyper-simplified things