from
Sat Aug 26 2023 02:03:44 (8 hours)
# 1.
Jaksland, Rasmus (2023) Distinguishing two (unsound) arguments for quantum social science. European Journal for Philosophy of Science. ISSN 1879-4912
Send To > Keep unreadDelete
from
by
Moisés Bermejo Morán, Alejandro Pozas-Kerstjens, and Felix Huber
Fri Aug 25 2023 18:00:00 (16 hours)
# 2.
Author(s): Moisés Bermejo Morán, Alejandro Pozas-Kerstjens, and Felix Huber
Which nonlocal correlations can be obtained, when a party has access to more than one subsystem? While traditionally nonlocality deals with spacelike separated parties, this question becomes important with quantum technologies that connect devices by means of small shared systems. Here, we study Bel…
[Phys. Rev. Lett. 131, 080201] Published Fri Aug 25, 2023
Send To > Keep unreadDelete
from
by
Arkady Bolotin
Fri Aug 25 2023 10:07:14 (1 day)
# 3.
Conventional wisdom holds that any region of 3-space contains infinitely many points, and the Planck length scale determines the uncertainty in every measurement of distance between two separate points. Against such a backdrop, this uncertainty may be interpreted as resulting from either foaminess or discreteness of 3-space. But, as it is demonstrated in the present paper, neither of those interpretations is consistent with the holographic principle. In the paper it is shown that the statement “The holographic principle holds true” and the statement “Each region in 3-space contains only a finite number of points” are logically equivalent.
Send To > Keep unreadDelete
from
by
Igor Salom
Fri Aug 25 2023 10:07:14 (1 day)
# 4.
The ideas and results that are in the background of the 2022 Nobel Prize in physics had an immense impact on our understanding of reality. Therefore, it is crucial that these implications reach also the general public, not only the scientists in the related fields of quantum mechanics. The purpose of this review is to attempt to elucidate these revolutionary changes in our worldview that were eventually acknowledged also by the Nobel’s committee, and to do it with very few references to mathematical details (which could be even ignored without undermining the take-away essence of the text).
We first look into the foundational disputes between Einstein and Bohr about the nature of quantum mechanics, which culminated in the so-called EPR paradox — the main impetus for all the research that would ensue in this context. Next, we try to explain the statement of the famous Bell’s theorem — the theorem that relocated the Einstain-Bohr discussions from the realm of philosophy and metaphysics to hard-core physics verifiable by experiments (we also give a brief derivation of the theorem’s proof). Then we overview the experimental work of the last year’s laureates, that had the final say about who was right in the debate. The outcome of these experiments forced us to profoundly revise our understanding of the universe. Finally, we discuss in more detail the implications of such outcomes, and what are the possible ways that our worldviews can be modified to account for the experimental facts. As we will see, the standard mechanist picture of the universe is no longer a viable option, and can be never again. Nowadays, we know this with certainty unusual for physics, that only a strict mathematical theorem could provide.
Send To > Keep unreadDelete
from
by
Salvador D. Escobedo
Fri Aug 25 2023 10:07:12 (1 day)
# 5.
Both relativistic mechanics and Newtonian mechanics are based on principles that have ontological implications. We propose a series of formalisms that rigorously define the ontology underlying mechanical theories, in order to clarify and formally establish the ontology of the physics of motion. Special attention has been paid to relativistic theories. Through the proposed methodology, the concept of ontological consistency is developed and the conditions required for such consistency to be satisfied in any theory are established. In particular, the consistency test is performed for Newtonian mechanics, special relativity theory, and general relativity theory.
Send To > Keep unreadDelete
from
by
J. B. Formiga, João Duarte
Fri Aug 25 2023 10:06:57 (1 day)
# 6.
The lack of a well-established solution for the gravitational energy problem might be one of the reasons why a clear road to quantum gravity does not exist. In this paper, the gravitational energy is studied in detail with the help of the teleparallel approach that is equivalent to general relativity. This approach is applied to the solutions of the Einstein-Maxwell equations known as $pp$-wave spacetimes. The quantization of the electromagnetic energy is assumed and it is shown that the proper area measured by an observer must satisfy an equation for consistency. The meaning of this equation is discussed and it is argued that the spacetime geometry should become discrete once all matter fields are quantized, including the constituents of the frame; it is shown that for a harmonic oscillation with wavelength $\lambda_0$, the area and the volume take the form $A=4(N+1/2)l_p^2/n$ and $V=2(N+1/2)l_p^2\lambda_0$, where $N$ is the number of photons, $l_p$ the Planck length, and $n$ is a natural number associated with the length along the $z$-axis of a box with cross-sectional area $A$. The localization of the gravitational energy problem is also discussed. The stress-energy tensors for the gravitational and electromagnetic fields are decomposed into energy density, pressures and heat flow. The resultant expressions are consistent with the properties of the fields, thus indicating that one can have a well-defined energy density for the gravitational field regardless of the principle of equivalence.
Send To > Keep unreadDelete
from
Fri Aug 25 2023 02:02:13 (1 day)
# 7.
Wenmackers, Sylvia (2023) Uniform probability in cosmology. [Preprint]
Send To > Keep unreadDelete
from
by
Sylvia Wenmackers
Thu Aug 24 2023 10:40:43 (1 day)
# 8.
Problems with uniform probabilities on an infinite support show up in contemporary cosmology. This paper focuses on the context of inflation theory, where it complicates the assignment of a probability measure over pocket universes. The measure problem in cosmology, whereby it seems impossible to pick out a uniquely well-motivated measure, is associated with a paradox that occurs in standard probability theory and crucially involves uniformity on an infinite sample space. This problem has been discussed by physicists, albeit without reference to earlier work on this topic. The aim of this article is both to introduce philosophers of probability to these recent discussions in cosmology and to familiarize physicists and philosophers working on cosmology with relevant foundational work by Kolmogorov, de Finetti, Jaynes, and other probabilists. As such, the main goal is not to solve the measure problem, but to clarify the exact origin of some of the current obstacles. The analysis of the assumptions going into the paradox indicates that there exist multiple ways of dealing consistently with uniform probabilities on infinite sample spaces. Taking a pluralist stance towards the mathematical methods used in cosmology shows there is some room for progress with assigning probabilities in cosmological theories.
Send To > Keep unreadDelete
from
by
Hanoch Ben-Yami
Thu Aug 24 2023 10:40:42 (1 day)
# 9.
I explain in what sense the structure of space and time is probably vague or indefinite, a notion I define. This leads to the mathematical representation of location in space and time by a vague interval. From this, a principle of complementary inaccuracy between spatial location and velocity is derived, and its relation to the Uncertainty Principle discussed. In addition, even if the laws of nature are deterministic, the behaviour of systems will be random to some degree. These and other considerations draw classical physics closer to Quantum Mechanics. An arrow of entropy is also derived, given an arrow of time. Lastly, chaos is given an additional, objective meaning.
Send To > Keep unreadDelete
from
by
Jonte R. Hance, Sabine Hossenfelder
Wed Aug 23 2023 09:48:08 (3 days)
# 10.
In a recent paper (Phys. Rev. A 105, 042220 (2022)), Daley et al claim that superdeterministic models are disfavoured against standard quantum mechanics, because such models overfit the statistics of a Bell-type experiment which the authors conducted. We argue here that their claim is based on a misunderstanding of what superdeterministic models are.
Send To > Keep unreadDelete
from
Wed Aug 23 2023 00:39:51 (3 days)
# 11.
Hazelwood, Caleb (2023) Newton’s “Law-First” Epistemology and “Matter-First” Metaphysics. [Preprint]
Send To > Keep unreadDelete
from
by
Jonte R. Hance, James Ladyman, John Rarity
Tue Aug 22 2023 11:02:56 (3 days)
# 12.
We explore how one might detect the dynamical quantum Cheshire cat proposed by Aharonov et al. We show that, in practice, we need to bias the initial state by adding/subtracting a small probability amplitude (`field’) of the orthogonal state, which travels with the disembodied property, to make the effect detectable (i.e. if our initial state is $|\uparrow_z\rangle$, we need to bias this with some small amount $\delta$ of state $|\downarrow_z\rangle$). This biasing, which can be done either directly or via weakly entangling the state with a pointer, effectively provides a phase reference with which we can measure the evolution of the state. The outcome can then be measured as a small probability difference in detections in a mutually unbiased basis, proportional to this biasing $\delta$. We show this is different from counterfactual communication, which provably does not require any probe field to travel between sender Bob and receiver Alice for communication. We further suggest an optical polarisation experiment where these phenomena might be demonstrated in a laboratory.
Send To > Keep unreadDelete
from
Tue Aug 22 2023 00:44:31 (4 days)
# 13.
Chen, Elliott D. (2023) Newtonian Gravitation in Maxwell Spacetime. [Preprint]
Send To > Keep unreadDelete
from
by
Partha Ghose
Mon Aug 21 2023 11:28:54 (4 days)
# 14.
As we approach the centenary of the discovery of quantum statistics in 1924, it is important to revisit Bose’s original derivation of Planck’s law usually ignored in most standard presentations of Bose-Einstein statistics. It introduced not only the novel concept of the indistinguishability of photons but also of their intrinsic spin, a fact unknown to most physicists.
Send To > Keep unreadDelete
from
Mon Aug 21 2023 07:46:50 (5 days)
# 15.
Krause, Décio (2023) The underlying logic is mandatory also in discussing the philosophy of quantum physics. [Preprint]
