Causality from outside Time

CSR: Culture, Science and Religion Causality from outside Time pagina 1 5-1-2019
Driessen.Alfred@gmail.com

Content
Introduction
Time in Relativity
Time in Quantum Mechanics
Conclusions

The demon of Laplace (1794-1827)
We have to consider the actual state of the
universe as the effect of its previous state, and as
the cause of the state that will follow.
Imagine an intelligent being which, at a
certain time, would know all the forces at
work in nature, and the respective
location of all the beings that compose it.
If it were powerful enough to analyze these data,
it could embrace together in the same formula
the movements of the largest bodies of the
universe and those of the lightest atom. Nothing
would be uncertain for this intelligent being and
both the future and the past would be present to
its eyes.
A Philosophical Essay on Probabilities, 1814

Causality
classical philosophy (Aristotle, Aquinas)
whatever is moved is moved by another or whatever is
changed is changed by another.
principle of causality
David Hume (1711-1776)
cause: an object followed by another, and where all the objects
similar to the first are followed by objects similar to the second.
Concerning Human Understanding.
Laplace (1794-1827)
We have to consider the actual state of the universe as the effect
of its previous state, and as the cause of the state that will follow.
Stephen Hawking (1942-2018)
Within the universe, you always explained one event as being
caused by some earlier event.
A brief history of time.

Effect always sperated in time by cause?
Stephen Hawking:
Within the universe, you always explained
one event as being caused by some earlier
event.
A brief history of time.
see discussion in Driessen, Acta Philosophica, 1995, 4, 83-93
Is this true in the light of modern physics?
relativity
before/after not uniquely defined
Eternity is no time at all, for a photon, (Penrose 2011)
quantum mechanics
final state symmetrical with initial state
delayed choice even after billions of years (Wheeler)

Content
Introduction
Time in Relativity
Conclusions

present:
space-like separated
from origin
future/past:
time-like separated from
origin
event at origin:
-- is caused by events in
the past light cone
-- has causal effects on
events in the future light
cone
Space-time diagram

Space-time diagram (1)
present:
space-like separated from origin
future/past:
time-like separated from
origin

Special and general relativity
light cone in special
relativity
light cone in
general relativity
(curved space)
figures from Penrose
Cycles of Time,
Random House,
London 2010

Tilting of the light cone (from Penrose
2010)
light cone tilted by speed of two walkers passing at event X;
at Andromeda (distance 2.2 lightyears), event (B) weeks earlier
than event (A)
figure from Penrose,
Cycles of Time,
Random House, London 2010

Tilting of the light cone by gravity
Light cones tilted by a strong
gravity field originating from a
starting blackhole as a function
of time.
figure from Penrose,
Cycles of Time,
Random House, London 2010

Time dilatation nearby a black hole
speed of light c is
constant in all
coordinate systems,
==> if x becomes
smaller, also t
diminishes
accordingly:
(gravitational) time
dilatation
figure based on
Penrose 2010
t
x
antconstc t
x
t
x

A clock visible at light-years distance
nano-clock: excited atom or molecule
emits radiation at a certain frequency
cosmological red shift:
due to time dilatation of rapidly
moving objects:
extreme case: background radiation
gravitational red shift
due to time dilatation nearby a heavy
mass (curvature of space, rotation of
light-cone)
extreme case: horizon of black hole

train at rest:
at three different moments
long train:

moving train:
long train:

new coordinates of the
moving train
moving train:
long train:

<= time line of train
consider two events
1: at origin
2: outside the light cone
There is an inertial system
where these are simultaneous
example
a traveler in an extremely long
moving train needs only to ask
his colleague at the wagon
at event 2.

<= time-line of the train
consider two events
1: at origin
2: inside the light cone
where these are at the same
place
example
a traveler in an extremely long
moving train needs only to
look out the window and
wait to see the event.

<= time line of train with speed c
011/1 22
 ttct 
consider two events
1: at origin
2: on the light cone
where these are simultaneously
at the same place
example
as before, event at the same
place, in addition: because
of time contraction:
interval of time is zero

consequence for a
photon:
In the coordinate system of
the photon, the event of
emission and absorption is:
-- instantaneously
-- without distance
emission absorption
<= time-line of photon

Penrose about photons and time
lecture in University of Leiden 2011
The point is that, according to a massless particle, the
passage of time is as nothing (2010).
Eternity is no time at all, for a photon (2011).

Content
Introduction
Time in Relativity
Conclusions

Collapse of wavefunction at double-slit
Results of double-slit experiments
with electrons (Dr. Tonomura) taken at
four increasing sampling periods;
each dot is caused by absorption of a
single electron and represents a “col-
lapsed” wavefunction at the detection
screen.
Waves (representative for
wavefunction of photons,
electrons, protons, atoms,
etc.) at a double slit.

Collapse of wavefunction at double-slit
Experiments by Guerreiro et al.
Physics Letter A 376, 2174-2177
Challenges:
- if wavefunction collapses at a
point, the probability at others
points is immediately set zero.
- where is the decision taken, -
- at the source?
-- at the detector?
-- in-between?
source: single photon
BS: beamsplitter, A and B: single photon detectors
Result (as expected)
either detector A or B is clicking,
nonlocality is confirmed
see also discussion in:
A. Driessen, Evidence for nonlocality
and nontemporality of a single photon
arXiv:1707.08034
source

measuring individual photons from a quasar whose image has been
split in two by a galaxy acting as a gravitational lens.
Final state:
1) interference set-up: photon follows both paths;
2) telescope view: photon takes a unique path.
delayed choice made after billions of years
Wheeler's proposal,
experimentally confirmed
(Jacques et al. 2007)
A Gedanken-experiment by Wheeler 1978

Gravitational lens at 9.5 light-year
gravitational lens: ~1011 mass of sun at 9.5 light-year
source galaxy: ~108 mass of sun at 11.5 light-year,
magnified 40x,
appears as ring with 4 pronounced images
Van der Wel et al. 2013 (arXiv: 1309.2826v1)

delayed choice for photon path
set-up 1 set-up 2
telescope picture: interference,
which-way information no which-way information
decision more than 11x109 years delayed

BS: beamsplitter; BSinput fixed; Bsoutput removable triggered by Quantum Noise after
the photon entered the interferometer, switching time: 40 ns.
Path 1 and Path 2: 48 m, flight duration for photon: 160 ns
detectors: detection gate 40 ns; single-photon pulse: 44 ns, repetition rate 238 ns
Science, Feb 2007, 315, pp. 966-968
Wheeler confirmed (Jacques et al. 2007)

Timing of the “delayed-choice” experiment, represented as a space-time diagram

Result of the delayed-choice
experiment:
a) beamsplitter switched on
b) beamsplitter switched off

Content
Introduction
Time in Relativity
Conclusions

Adriaan Fokker, 1887-1972)
A. D. Fokker, Universiteit Leiden (1965)
Perhaps the deepest enigma brought to light by
chronogeometry is the occurrence of zero
intervals, connecting events which are located
by observers with spatial distance and temporal
duration between them. Zero interval means no
separation at all, an immediate transmission of
momentum and energy, as if there were
contiguity……
The mathematical formula is quite simple and
plain, nevertheless it relates to one of God's
secrets and implies His sempiternal ubiquitous
presence.
A.D. Fokker, Time and Space Weight and Inertia,
Pergamon Press, Oxford, 1965

Fermi’s Golden rule
Sommerfeld 1930 (Scientia 1930 II, p 85; translation by AD)
When on occasions I spoke about a new,
conditioned causality, it was mathematically
founded. It appears namely that we have to calculate
emission by a formula, in which the initial and final
condition of the atom enters equally and
symmetrically.
(...) By the way, this is not completely new. Aristotle
considered besides the efficient cause also the final
cause.
taken from:
Snoeks et al. PRL, 74,
13, 1995, p 2459

problems with causality of Laplace
We have to consider the actual state
of the universe as the effect of its
previous state, and as the cause of
the state that will follow.
Where could the Laplace demon be
located?
in relativity: there is no preferred light
cone, each with a different metric for
time;
in QM: causal effects are not restricted
to the initial state, but include also the
final state (sometimes called the
observer).

Causality without referring to time
In both cases:
it would be advisable to broaden the concept of causality to
include influences from outside space and time.
Approach in classical philosophy (Aristotle, Aquinas)
whatever is moved is moved by another or whatever is
changed is changed by another.
Conclusions from this study:
There are causes beyond the realm of science,
- they are not observable by physical or scientific means
- the effects of these causes, however, are observable by
physical and scientific means.
Physics is not complete.
Possible causes of that type:
- First Cause
- human free wil

This talk has been presented at the
21th International Interdisciplinary Seminar
Science and Society: Defining what is human
Netherhall House, London, 5-1-2019

Causality from outside Time

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