Principles in Physics

Session

Session

27 Mar 2023, 15:30

O.07.24 (Bergische Universität Wuppertal)

10. Covariance, Equivalence and Locality: Reconsidering The Methodological Lesson from General Relativity

Guy Hetzroni (The Open University of Israel)

27/03/2023, 15:30

Einstein’s general theory of relativity is often presented as a significant turning point indicating a methodological shift in theoretical physics towards mathematically-based patterns of reasoning, and theories populated by abstract mathematical structures constructed using non-empirical guiding principles. This approach, which was advocated inter alia by Einstein himself from the mid 1920s,...

52. The Principle of Complete Positivity and the Open Systems View

Michael Cuffaro (Munich Center for Mathematical Philosophy)

27/03/2023, 16:05

The principle that the dynamics of any open system should be derivable from the fundamental automorphic dynamics of a larger closed system represents what we will be calling, in this talk, the closed systems view. The closed systems view is deeply entrenched in physics. Standard quantum theory (ST) is no exception, and within it the closed systems view finds expression in the principle of...

6. The reverse side of the BRST coin: String-localized quantum field theory

Karl-Henning Rehren (Institute for Theoretical Physics, Göttingen University)

27/03/2023, 16:40

Gauge symmetry is most successful at predicting the structure of all interactions among particles in the Standard Model. Yet, among the principles of QFT: causality, covariance, probability (Hilbert space), it stands out: it addresses exclusively non-observable entities (gauge potentials and Fermi fields). It may be doubted how “fundamental” such a principle is from an ontological point of...

58. Vague ideas

Márton Gömöri

27/03/2023, 17:15

One sense in which a physical claim may qualify as a “principle”, as opposed to a law for example, is that it expresses a typically general-sounding but vague idea. The talk will deliver a case study for this notion. While there is a longstanding discussion about the interpretation of the extended, general principle of relativity, there seems to be a consensus that the special principle of...

56. Are Physics Principles Needed to Justify Theories in Space-time & Gravity?

J. Brian Pitts

28/03/2023, 11:25

Scientific principles in physics can be understood as useful in the context of discovery, but rarely crucial in the context of justification (to recall a distinction due to Hans Reichenbach)---at least not in the physics of space-time and gravity, where principles have seemed particularly important. Consequently neither the need to evaluate principles philosophically nor the apparent failure...

57. The Meaning of Quantum Mechanics as a Principle Theory

Iulian Toader

28/03/2023, 12:00

In the context of information-theoretical reconstructions of quantum mechanics,
Einstein’s distinction between constructive and principle theories is typically believed
to support arguments against realist (or ψ-ontic) interpretations of quantum mechanics.
For instance, one argues that since such interpretations have neither the explanatory
power of a principle theory, nor the explanatory...

54. Cassirer’s Theory of Physical Principles and the Route to Schrödinger’s Undulatory Mechanics

Benedetta Spigola (University of Roma Tre)

28/03/2023, 16:25

In this paper I will analyse Cassirer’s conception of physical principles in order to argue that (i) they are universal, meaning that they do not entail any definite content belonging to a particular phenomenon or a specific region of physical domain, rather they refer to the algebraic operations according to which we decipher and understand classes of physical phenomena; (ii) physical...

11. The global principle of relativity

Jochum Van Der Bij (Albert Ludwigs Universitaet Freiburg (DE))

28/03/2023, 17:00

I describe a new principle of relativity
involving the topology of space-time.
On its basis I derive the following:
1) the gauge group of nature must be SU(5)
2) there must be exactly 3 generations of fermions
3) after symmetry breaking the standard model is
the only possible low-energy theory in the chiral sector
4) The dark matter of the universe consists of
Dirac triplets, or at...

14. Dreams of a Physics Without Lagrangians: The Long S-Matrix Programme

James Duncan Fraser

29/03/2023, 11:25

Differential time-evolution equations have long been the paradigm examples of laws of nature. Yet, the 20th century saw the rise to prominence of atemporal conditions and principles in many areas of physics. This paper looks at a particularly radical strand of this tendency: the attempt to do away with time-evolution equations entirely in relativistic quantum theory. I make a case for...

62. Axioms as Principles: The Case of Quantum Field Theory

Michael Stöltzner (USC)

29/03/2023, 12:00

Physical principles separate the physical from the unphysical. They come in various forms and functions. The naturalness principle, for instance, is primarily a heuristic for model builders in present day elementary particle physics whose specific form and validity has been broadly debated recently. In some cases, such as Mach’s principle, debates last forever and extend into genuinely...

61. A Functional Classification of Physical Principles, Illustrated by the Theory of Relativity

Samuel Fletcher (University of Minnesota, Twin Cities)

29/03/2023, 12:35

Physical principles are statements pertaining to physical theories, the possibilities they represent, and what can be inferred from them. One can classify principles in many cross-cutting ways, but doing so according to the principles’ scientific function can be particularly illuminating, illustrating the diversity of roles they can play, and how those roles can change over time. Using the...