没有合适的资源?快使用搜索试试~ 我知道了~
资源推荐
资源详情
资源评论
Journal of Modern Physics, 2018, 9, 1697-1711
http://www.scirp.org/journal/jmp
ISSN Online: 2153-120X
ISSN Print: 2153-1196
DOI:
10.4236/jmp.2018.98106 Jul. 31, 2018 1697 Journal of Modern Physics
Unravelling the Quantum Maze
María Esther Burgos
Department of Physics, University of Los Andes, Mérida, Venezuela
Abstract
The restoration of philosophical realism as the basis of quantum mechanics is
the main aim of the present study. A spontaneous projection approach to
quantum theory previously formulated achieved this goal in cases where the
Hamiltonian does not depend explici
tly on time. After discussing the most
relevant flaws of orthodox quantum mechanics, a formulation of the sponta-
neous projections approach in the general case is introduced. This approach
yields experimental predictions which in general coincide with those
of the
orthodox version and overcomes its main flaws.
Keywords
Quantum Weirdness, Quantum Measurements, Spontaneous Quantum
Jumps
1. Introduction
The foundations of quantum mechanics were laid in the period 1900-1926. Some
of its achievements were introduced and discussed at the Fifth Solvay Congress
(1927). Even though the theory seemed bizarre, it was accepted by the majority
of participants at this meeting ([1], pp. 109-121). In 1930 Paul Dirac published
the first formulation of quantum mechanics [2]. Two years later John von Neu-
mann published
Mathematische Grundlagen der Quantenmechanik
[3]. Quan-
tum mechanics was born.
These first versions of the theory share two characteristics: 1) The state vector
ψ
(wave function
ψ
) describes the state of an
individual system
. 2) They in-
volve two laws of change of the system’s state: Spontaneous (natural) processes,
governed by the Schrödinger equation; and measurement processes, ruled by the
projection postulate. This postulate gives an account for projections (collapses,
reductions or quantum jumps) caused by measurements. Many other versions of
quantum theory followed. Those where
ψ
describes the state of an individual
How to cite this paper:
Burgos, M.E.
(201
8) Unravelling the Quantum Maze
.
Journal of Modern Physics
,
9
, 1697-1711.
https://doi.org/10.4236/jmp.2018.98106
Received:
June 15, 2018
Accepted:
July 28, 2018
Published:
July 31, 2018
Copyright © 201
8 by author and
Scientific
Research Publishing Inc.
This work is licensed under the Creative
Commons Attribution International
License (CC BY
4.0).
http://creativecommons.org/licenses/by/4.0/
Open Access
M. E. Burgos
DOI:
10.4236/jmp.2018.98106 1698 Journal of Modern Physics
system
and
the projection postulate is included among its axioms are generally
called standard, ordinary or orthodox quantum mechanics (OQM), sometimes
referred to as the
Copenhagen Interpretation
.
From its inception OQM, and in particular its projection postulate, was the
target of merciless criticism. Many scientists denounced what they considered its
flaws. Among them, 1) it is incompatible with determinism; 2) it implies a kind
of action-at-a-distance; and 3) it renounces philosophical realism. In addition,
OQM presents a conflict with conservation laws which has been largely ignored
[4] [5] [6] [7] [8] and carries the seeds of incoherence and contradictions [9] [10].
In 1931 Albert Einstein rightfully proclaimed: “the belief in an external world
independent of the perceiving subject is the basis of all natural science” [11]. The
restoration of philosophical realism as the basis of quantum mechanics is hence
worth being pursued. The corresponding change of formalism should be realized,
however, keeping as much as possible the experimental predictions of OQM, a
theory imposingly successful [12].
This is the main aim of the spontaneous projection approach (SPA), a version
of quantum theory previously formulated for cases where the Hamiltonian does
not depend explicitly on time. It achieved this goal to a certain degree: it does
not modify the Schrödinger equation and recovers a version of Born’s postulate
where no reference to measurements is made [13] [14] [15]. But the fact that it
cannot account for cases where the Hamiltonian depends explicitly on time was
a flaw which became increasingly apparent during our critical review of time
dependent perturbation theory (TDPT) and forced us to conclude that
OQM
weirdness is not limited to the measurement problem
[9] [10].
The version of SPA introduced in the present paper is more general than the
previous one for it includes cases where the Hamiltonian depends explicitly on
time. It keeps, however, the essential traits of SPA first version and yields, as far
as we can see, the same experimental predictions obtained from OQM.
2. Philosophical Realism, Quantum Measurements and
Scientific Problems
We uphold philosophical realism. We did in the first version of SPA and adopt
the same epistemology as the basis of our present, more elaborated and general
formulation of SPA. Our philosophical starting point can be stated as follows: 1)
the things physics is about are supposed to exist, whether they are observed or
not; 2) every scientific theory represents things through conceptual models; and
3) the adequacy of a theory (and corresponding models) to the things it refers to
must take experimental results into account. In agreement with the philosophi-
cal point of view we adopt, “
there are no definitive theories or models in
(
factual
)
science
,
because scientific knowledge is always of a hypothetical and never of a
final nature” [16] [17]. More on this subject in ([18], p. 86).
According to Mario Bunge, “the main epistemological problem about quan-
tum theory is whether it represents real (autonomously existing) things, and
M. E. Burgos
DOI:
10.4236/jmp.2018.98106 1699 Journal of Modern Physics
therefore whether it is compatible with epistemological realism. The latter is the
family of epistemologies which assume that a) the world exists independently of
the knowing subject, and b) the task of science is to produce maximally true
conceptual models of reality…” ([19], pp. 191-192). He adds: “The main pillar of
the non-realist interpretations of quantum theory is a certain view on measure-
ment and on the projection (reduction) of the state function that is involved in
measurement… [Sometimes] ‘measurement’ is misused to denote
any interac-
tion
of an entity with the environment… However, the worst misconception of
measurement is its identification with the subjective experience of
taking cog-
nizance
of the outcome of measurement” ([19], pp. 192-193). For instance, in
von Neumann’s view, a complete measurement involves the consciousness of the
observer ([1], pp. 481-482) ([20], pp. 418-421). “By assuming that observation
escapes the laws of physics… the orthodox view treats measurement as an un-
physical process…” ([19], p. 200).
In his answer to the question “what can be observed?” Bell quotes Einstein
saying “it is theory which decides what is ‘observable’. I think he was
right—‘observation’ is a complicated and theory-laden business. Then
that no-
tion should not appear in the formulation of fundamental theory
” ([21], p. 208;
emphases added). Bell exposes to ridicule the supposedly necessary intervention
of an observer to cause projections when he asks: “What exactly qualifies some
physical system to play the role of ‘measurer’? Was the wave function of the
world waiting to jump for thousands of millions of years until a single-celled
living creature appeared? Or did it have to wait a little longer, for some better
qualified system... with a PhD? If the theory is to apply to anything but highly
idealized laboratory operations, are we not obliged to admit that more or less
‘measurement-like’ processes are going on all the time, more or less everywhere?
Do we have jumping all the time?” ([21], p. 209).
Some authors dealing with the measurement problem avoid reference to the
observer, but assume that measuring devices are macroscopic. Concerning this
hypothesis Max Jammer highlights: “as long as a quantum mechanical one-body
or many-body system does not interact with a macroscopic object, as long as its
motion is described by the deterministic Schrödinger time-dependent equation,
no events could be considered to take place in the system… If the whole physical
universe were composed only of microphysical entities, as it should be according
to the atomic theory, it would be a universe of evolving potentialities (time-
dependent
ψ
-functions) but not of real events” ([1], p. 474).
A few authors have considered the possibility that projections may happen at
the microscopic level, that they are not necessarily the result of the interaction
between a quantum system and a macroscopic object [22] [23]. We agree. Col-
lapses are a kind of spontaneous processes occurring in nature. In order to take
place, they require neither the intervention of observers nor the interaction of a
microscopic (quantum) system with a macroscopic (classical) measuring device
[13]. Reductions may also happen in tiny isolated systems.
剩余14页未读,继续阅读
资源评论
weixin_38643127
- 粉丝: 8
- 资源: 921
上传资源 快速赚钱
- 我的内容管理 展开
- 我的资源 快来上传第一个资源
- 我的收益 登录查看自己的收益
- 我的积分 登录查看自己的积分
- 我的C币 登录后查看C币余额
- 我的收藏
- 我的下载
- 下载帮助
安全验证
文档复制为VIP权益,开通VIP直接复制
信息提交成功