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bawolff
I don't understand what the thesis of this article is.

What is quantum monism? what is the soul of physics? Why does the soul of physics need saving? What does it need saving from?

After reading this article i still have no idea. Did this make sense to anyone else? Am i just dense?

Schiphol
>the soul of science [is] the conviction that there is a unique, comprehensible and fundamental reality.

>According to quantum monism, the fundamental layer of reality is not made of particles or strings but the universe itself—understood not as the sum of things making it up but rather as a single, entangled quantum state.

joe-collins
That sounds rather similar to superdeterminism.
texaslonghorn5
Not really, superdeterminism postulates that the measurement outcomes are guaranteed.

Here, you could imagine the universe as being operated on by some giant Hamiltonian operator with a basis of eigenstates, and then the amplitudes will just deterministically evolve according to the Schrödinger equation. But the amplitudes only reveal information about probabilities of measurement, not measurement outcomes themselves.

[How such a measurement could occur (coming from outside this universe system) isn't physically clear to me but isn't relevant either.]

bawolff
How is this not begging the question? "The universe is the universe" is not a satisying answer to, well, any question really.
slowmovintarget
It is not expressing a tautology, it is saying the universe is a single quantum field. Basically, a single coordinate in some Hilbert space.
bawolff
And the consequences of that are what precisely? For that matter, what would the consequences be if it wasn't true?
ur-whale
>It is not expressing a tautology, it is saying the universe is a single quantum field

Probably should have said that, then.

slowmovintarget
Well... it did. I couldn't distinguish quantum monism from Everettianism with my lay-person's understanding of the physics. I've gobbled up Sean Carroll's Biggest Ideas in the Universe video series on YouTube, and read his popular books on the matter, but that's the extent of my knowledge.
mxkopy
X = X doesn’t seem to be either, but it took some thousands of years for us to grasp the ramifications of such a statement
padjo
Who is this article pitched at? It seems to veer from explaining very basic things to assuming advanced knowledge and ultimately winds up saying that the fundamental layer of reality is the universe, which feels pretty tautological.
slowmovintarget
It should also be marked 2019 as stareatgoats indicates.
hackandthink
It reminds me of Sean Carrols Hilbert Space Fundamentalism.

Sean M. Carroll: Reality as a Vector in Hilbert Space

https://arxiv.org/abs/2103.09780

im3w1l
Looking at the date on that article, he isn't the first to propose the idea. I remember hearing about "The Church of the larger Hilbert space" many years ago.
westurner
Hilbert space https://en.wikipedia.org/wiki/Hilbert_space :

From sympy.physics.quantum.hilbert https://github.com/sympy/sympy/blob/master/sympy/physics/qua... :

  __all__ = [
    'HilbertSpaceError',
    'HilbertSpace',
    'TensorProductHilbertSpace',
    'TensorPowerHilbertSpace',
    'DirectSumHilbertSpace',
    'ComplexSpace',
    'L2',
    'FockSpace'
  ]
From sympy.physics.quantum.operator https://github.com/sympy/sympy/blob/master/sympy/physics/qua... :

  __all__ = [
    'Operator',
    'HermitianOperator',
    'UnitaryOperator',
    'IdentityOperator',
    'OuterProduct',
    'DifferentialOperator'
  ]
From SymPy.physics.quantum.operatorset https://github.com/sympy/sympy/blob/master/sympy/physics/qua... :

  """ A module for mapping operators to their corresponding eigenstates and vice versa
  It contains a global dictionary with eigenstate-operator pairings.
  If a new state-operator pair is created,
  this dictionary should be updated as well.
  It also contains functions operators_to_state and state_to_operators for mapping between the two. These can handle both classes and instances of operators and states. 
  See the individual function descriptions for details.
  TODO List:
  - Update the dictionary with a complete list of state-operator pairs
  """
From sympy.physics.quantum.represent https://github.com/sympy/sympy/blob/master/sympy/physics/qua... :

  """Logic for representing operators in state in various bases.
  
  TODO:
  * Get represent working with continuous hilbert spaces.
  * Document default basis functionality.
  """
  # ...
  
  __all__ = [
    'represent',
    'rep_innerproduct',
    'rep_expectation',
    'integrate_result',
    'get_basis',
    'enumerate_states'
  ]
  
  # ...
  
  def represent(expr, **options):
      """Represent the quantum expression in the given basis.
"I am one with the universe"

From tequila/simulators/simulator_cirq https://github.com/tequilahub/tequila/blob/master/src/tequil... :

  from tequila.wavefunction.qubit_wavefunction import QubitWaveFunction
From tequila.circuit.qasm https://github.com/tequilahub/tequila/blob/master/src/tequil... :

> """ Export QCircuits as qasm code OPENQASM version 2.0 specification from:

> A. W. Cross, L. S. Bishop, J. A. Smolin, and J. M. Gambetta, e-print arXiv:1707.034...

MockObject
Why are you posting this?
westurner
Because there is a functional executable symbolic algebra implementation of such Hilbert spaces and their practical representations (and qubit applications) that's approachable because it's not ambiguous MathTeX without automated tests and test assertions.

Because it's easier to learn math things by preparing a notebook with MathTex and/or SymPy expressions with a MathTeX representation and then make test assertions about the symbolic expression and/or `assert np.allclose()` with real valued parameters after symbolic construction and derivation

Eratosthenes
I thought everything in physics was going great, all of our theories are extremely well-tested and there are absolutely no anomalies, inconsistencies, paradoxes, singularities, or unexplained parameters. A crisis? My word!