Quantum Theory of Fields and the Fabric of Space and Time. Status of ... Determinism with relation to free will .... sufficiently explained by the assumption of a.
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Status of Time in Physics Ramis Movassagh Department of Mathematics, MIT/Northeastern
September 17, 2012
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Outline
Time in the scientific methods Conception of time throughout history Space-time in physics Origin of space-time Measuring time Information and time Modern views of fabric of space-time
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Out - of - line
Time in psyche (perception/intensity) Time in religion Existence (now-ness, illusion of time) Reality Philosophy of time Management of time and its use Determinism with relation to free will Mythology
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
What is time?
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
What is time?
[mass noun] the indefinite continued progress of existence and events in the past, present, and future regarded as a whole - Oxford Dictionaries
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
What is time? [mass noun] the indefinite continued progress of existence and events in the past, present, and future regarded as a whole - Oxford Dictionaries
Time is the continuing sequence of events occurring in apparently irreversible succession from the past through the present to the future and a measure of the durations and frequencies of events and the intervals between them. -Wikipedia
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
What is time? [mass noun] the indefinite continued progress of existence and events in the past, present, and future regarded as a whole - Oxford Dictionaries
Time is the continuing sequence of events occurring in apparently irreversible succession from the past through the present to the future and a measure of the durations and frequencies of events and the intervals between them. -Wikipedia
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Less controversial Wiki hits
"time is what clocks measure" "time is what keeps everything from happening at once" Comment: Whoever wrote this didn’t believe in causality.
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
The Scientific Method
Key element in science is experiment Confidence in experiment requires reproducibility There is a tacit assumption of homogeneity in time when performing experiments.
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
The Scientific Arrogance
Zealous belief in comprehensibility of nature The Eventual Goal of Science is to provide a single theory that describes the whole universe - S. Hawking, Briefer History of Time Demanding a unified view especially developed in countries that were monotheistic (e.g. unifying forces, string theory etc.)
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Physics Physics is mainly concerned with the state and evolution in time of material particles and fields given the couplings among them.
Newton's 2nd “law of motion”
F=ma=mx
Physics (empirical)
Ramis Movassagh
Math (differential equation)
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Physics
Physics Physics is mainly concerned with the state and evolution in time of material particles and fields given the couplings among them. t>0
t=0
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
(non) determinism
(non) determinism
Omar Khayyam (1048–1131)
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
(non) determinism
And the first Morning of Creation wrote What the Last Dawn of Reckoning shall read.
Omar Khayyam (1048–1131)
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Existence Static Existence: “Block Universe” t
Person B's Life events
y
Person A's Life events
x
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Determinism Absolute, true and mathematical time, of itself, and from its own nature flows equably without regard to anything external, and by another name is called duration...
Sir Isaac Newton (1649 -1736) Principia
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Arrow of Time
Good References: ● ● ●
Ramis Movassagh
S. Carroll's talks and book Schrödinger, 'what is life?' H Price, Time Arrow (Phil.)
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Arrow of time
t0 Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Arrow of time
t0
Many ways of having such evolution
Ramis Movassagh
t>t0
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Arrow of time
?
t0
t>t0 Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Arrow of time
YES! “...You would have to wait a long time” - L. Boltzmann
t>t0
NOT Many ways of having such evolution
Ramis Movassagh
t0
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Micro vs. Macro States
Microstates: any particular configuration in the phase space Macrostate: sets of macroscopically indistiguishable microstates S = kB ln D Entropy is lack of information, lack of structure
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Phase Space Probabilities Second law of thermodynamics: time evolution of the state
S≥0 t > t0
t = t0
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
The second law of thermodynamics
Equilibrium is death for living matter
So why is the universe so complex (life, structure, etc.) ? ?
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
What is Life?
S
= kB ln D
D: amount of disorder
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
What is Life?
S
= kB ln D 1 Sdrawn = kB ln = −kB ln D D D: amount of disorder
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Drawing order and pushing equilibrium away
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Drawing order and pushing equilibrium away
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Ludwig Boltzmann (1844 - 1906) ...That in Nature the transition from a probable to an improbable state does not happen equally often as the opposite transition, should be sufficiently explained by the assumption of a very improbably state of the whole universe surrounding us ...
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Universe: S(t0 )
Around big bang
Simple
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Universe S(t1 > t0 ) Around now: 1010 yrs
Around big bang
Simple
Complex
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Universe S(t2 > t1 ) 10 15 yrs
Simpler than now Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Universe S(t3 > t2 ) > 10 100 yrs an eternal vast emptiness
Simple Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Suggesting
Magnitude
Complexity
Entropy
Time Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Plan Physics
Einstein's relativity Preserves Causality, Determinism, ...
Quantum theory Inherently probabilistic, Heisenberg's uncertainty principle, ….
Partially reconciled to quantum theory of fields
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Plan Physics
Quantum theory
Einstein's relativity Preserves Causality, Determinism, ...
Inherently probabilistic, Heisenberg's uncertainty principle, ….
1
2
Partially reconciled to quantum theory of fields
3 These have profound consequences, which we will now explore Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Einstein's Relativity and Consequences
Good References: ●
● ●
Ramis Movassagh
S. Hawking, Briefer History of Time W. Rindler, 'Relativity' S. Weinberg, Gravitation
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Newton’s Universe
Absolute space Absolute time
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Newton’s Universe
Absolute space Absolute time Despite his equations implying relativity. Newton was severely criticized but he remained a tough cookie because he believed God is absolute =⇒ His space and time had to be!
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Albert Einstein
Time at and after Einstein
Albert Einstein (1879 - 1955) Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Absolute , equable, mathematical ...
Time
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Space-Time
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Space-Time Relative !
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Space-Time ق- elative !
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Birth of Special Relativity
AE was fascinate by Maxwell’s theory that unified E & M (constancy of speed of light) It took young and hungry Einstein’s imagination and confidence to hold on to this original line of thought despite various seeming paradoxes.
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Consequences of SR
Make mechanics consistent with Maxwell’s theory =⇒ Special Theory of Relativity ! Relativity of space and time. Nothing absolute about space or time No faster than light signal (causality). Equivalence of mass and energy: E = mc 2
Unified mechanics with Electromagnetism
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Consequences of SR
Make mechanics consistent with Maxwell’s theory =⇒ Special Theory of Relativity ! Relativity of space and time Nothing absolute about space or time No faster than light signal (causality). Equivalence of mass and energy: E = mc 2
⇔
m=
E c2
Unified mechanics with Electromagnetism
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Einstein’s Universe
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
A. Friedman Took Einstein’s equations at face value
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Friedman’s solution(s) of the Universe
I. Expands, slows down, contracts into a crunch II. Expands so rapidly that the gravitational attraction can never stop it (escape velocity) III. Expands rapid enough that it stops at infinite time, i.e., barely escapes the crunch doomsday None have a boundary.
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
So which is it?
Recent, we see that the expansion is accelerating =⇒ NONE OF THE FRIEDMAN solutions !
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
The “Big Bang”
A common feature of all solutions to Einstein’s equations is that, regardless of the future:
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
The “Big Bang”
A common feature of all solutions to Einstein’s equations is that, regardless of the future: At 13.7 Billion years ago the distance between neighboring galaxies must have been zero.
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
The “Big Bang”
A common feature of all solutions to Einstein’s equations is that, regardless of the future: At 13.7 Billion years ago the distance between neighboring galaxies must have been zero. All the universe must have been at a single point: the origin of space and time!
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Time Travel
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Traveling into the future
This is easy. Just wait
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Traveling into the future
This is easy. Just wait You can even fast forward into the future (so called twin paradox)
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
But can we travel into the past ?!
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Closed Time-like Curves
Closed Time-like Curves
Kurt Gödel: 1906 – 1978
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Closed Time-like Curves
Closed Time-like Curves ●
Arguably the greatest logician of all times.
●
Very difficult patient
●
Incompleteness Theorem
●
●
Finding an inconsistency in American constitution
Kurt Gödel: 1906 – 1978
Closed time like curves (CTC)
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
One way: Closed Time Like Curves
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
CTC: Features of Gödel’s solution
Solution implies that the whole universe is rotating Mathematical side effect: travel a great distance and come back to a different space-time point. e.g. come back to earth and a time in the past !
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
CTC: Features of Gödel’s solution
Solution implies that the whole universe is rotating Mathematical side effect: travel a great distance and come back to a different space-time point. e.g. come back to earth and a time in the past !
Good news is that : recent data suggests that there are no Gödel rotations, further his model doesn’t have expansion in it.
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
CTC: Features of Gödel’s solution
Solution implies that the whole universe is rotating Mathematical side effect: travel a great distance and come back to a different space-time point. e.g. come back to earth and a time in the past !
Good news is that : recent data suggests that there are no Gödel rotations, further his model doesn’t have expansion in it. Bad news ...
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
There are other ways
1
Faster than light. No go with GR.
2
Curve the space-time so much by gravitation that you create a singularity.
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Wormholes
Albert Einstein and Nathan Rosen (1935): create the bridges, In the same year: EPR predict entanglement !
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
A Wormhole in a 2D universe
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Quantum Fabric of Space-Time
F. Wilczek , various books S. Carroll's book N. Arkani-Hamed , various talks IAS talk 2011 recommended
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Consequences of QFT
E ∆E
= mc 2 ∼
1 ∆t
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Consequences of QFT
E ∆E
= mc 2 ∼
⇔
m=
E c2
1 ∆t
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Vacuum: Can it get any more boring?
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Vacuum: Can it get any more boring?
e- e+
ΔE~
1 Δt
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Vacuum: It's kinda of exciting? p-
e+ p+ e-
k+ k-
μ+ μ-
~ 10
-13
– 10
Ramis Movassagh
-16
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
This description of nature has been tremendously successful based on QFT Formulated by 1970's with fantastic set of predictions.
Now with Higgs having been verified, we have strong confidence that the standard model is an accurate description of nature to scales 10 -16
Some experiments are verified to a part in 1011
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
This description of nature has been tremendously successful based on QFT Formulated by 1970's with fantastic set of predictions.
eeff
10 -11 cm Verified to an accuracy of 1/1000
I. Levine et al. , Phys. Rev. Lett. 78, 424–427 (1997)
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Vacuum: Too EXCITING
Doom of Space Time
~ 10 -33 cm ~ 10 -43 sec
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Hell breaks loose at the Planck scale Planck time Planck mass Planck length (ℓP)
5.39121 × 10−44 s 2.17645 × 10−8 kg 1.616252×10−35 m
Numbers from wikipedia
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Quantum Mechanics & Relativity
Δ E ~ 1/ Δ t
Ramis Movassagh
E = m c2
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Quantum Mechanics & Relativity
Δ E ~ 1/ Δ t
E = m c2
Fluctuations become larger and larger at smaller scales.
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Quantum Mechanics & Relativity
Δ E ~ 1/ Δ t
E = m c2
Fluctuations become larger and larger at smaller scales.
Vacuum has energy: is a hot boiling soup of particles
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Quantum Mechanics & Relativity
Δ E ~ 1/ Δ t
E = m c2
Fluctuations become larger and larger at smaller scales.
Vacuum has energy: is a hot boiling soup of particles
Shorter distances give yet higher energies; i.e., higher energy density Λ
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Even if we don't go so small as the planck scale so we can meaningfully talk about space and time we still get a very large Λ
Predicts a Λ so large that the universe would expand a lot faster than observed
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Even if we don't go so small as the planck scale so we can meaningfully talk about space and time we still get a very large Λ
Predicts a Λ so large that the universe would expand a lot faster than observed
Λobserved ~ 10-120 Λtheory
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
How is it currently explained and “understood”? ? Believe it or not we do fine tuning :
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
How is it currently explained and “understood”? ? Believe it or not we do fine tuning :
Λobserved = Λtheory + Λ background Λtheory ~ - Λ background Where they agree to 120 decimal places and hence cancel !!!
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
How is it currently explained and “understood”? ? Believe it or not you do fine tuning :
Ju Th st ha ere pp en ! s
Λobserved = Λtheory + Λ background Λtheory ~ - Λ background Where they agree to 120 decimal places and hence cancel !!!
Ramis Movassagh
Status of Time in Physics
to be
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Anthropic Principle (idea): Sean Carroll’s picture
But why why? Best we got is the Anthropic Principle:
The fundamental physical constants necessary to accommodate conscious life
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Anthropic Principle (idea): Sean Carroll’s picture
But why why? Best we got is the Anthropic Principle:
The fundamental physical constants necessary to accommodate conscious life
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Clocks ●
●
Oldest of man's inventions to measure time intervals smaller than ones offered by nature (e.g., a day, a lunar cycle etc.) Signature of all clocks is periodicity
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Atoms Atoms are of the same identical kind. As far as we know they don't change their properties over time. They have 'discrete' energy levels Their transitions are invariants Provide a source for high frequency 'hatching' of time.
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Atoms Atoms are of the same identical kind. As far as we know they don't change their properties over time. They have 'discrete' energy levels Their transitions are invariants Provide a source for high frequency 'hatching' of time.
Atomic Clocks: also use periodicity !
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
An Atomic Transition
E±δE E
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
An Atomic Transition
E
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
An Atomic Transition
E
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
An Atomic Transition
E E
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Sharpen the precision Feed back To Drive the cavity
E
E ± δE E
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Sharpen the precision Feed back To Drive the cavity
E
~E E
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Sharpen the precision Feed back To Drive the cavity
E
~E E
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Sharpen the precision Feed back To Drive the cavity
E
~E E
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
State of art clocks
1
Fountain atomic clock: Microwave standars such as NIST-F1 caesium fountain loses a second in 100 million years
2
Quantum clocks: UV standard aluminum and beryllium ion clock loses a second in 3.7 billion years 1
3
1,121,015,393,207,857.4(7) Hz
In February 2010, NIST enhanced it using a single aluminum to get twice accuracy
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
What is time? [mass noun] the indefinite continued progress of existence and events in the past, present, and future regarded as a whole - Oxford Dictionaries Time is the continuing sequence of events occurring in apparently irreversible succession from the past through the present to the future and a measure of the durations and frequencies of events and the intervals between them. - Wikipedia
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
The World as a Fluctuation
Perhaps Boltzmann’s idea can be restored that each of these ’big bangs’ corresponds to a fluctuation in a grand-universe that is otherwise at equilibrium. Hence our world including lives, dreams and cosmology are none but an ephemeral fluctuation sparkling in a timeless existence
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Lastly... At this very moment I remain confused as to whether I should
ThankQ
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Lastly... At this very moment I remain confused as to whether I should
ThankQ or Thank you Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
So let me
1 √ { ThankQi 2
Ramis Movassagh
+
Thank youi }.
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
The Scientific Method
Key element in science is experiment Confidence in experiment requires reproducibility There is a tacit assumption of homogeneity in time when performing experiments. A good theory is characterized by the fact that it makes a number of predictions that could in principle be disproved or falsified by observation Karl Popper In science we are never right, we can only prove to be wrong.
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Existence “There are really four dimensions, three which we call the three planes Of Space and a fourth Time. There is however a tendency to draw an unreal distinction between the former three And the latter dimension because our consciousness moves intermittently in one direction along the latter from the beginning to the end of our lives” “That' said a very young man, making spasmodic efforts to relight his cigar over the lamp; 'that … very clear indeed.” H.G. Wells, The Time Machine (Chapter 2 SR , S. Weinberg, Gravitation)
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Cosmic Microwave Background (CMB)
We appear here 13.7 billion years later
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Cosmic Microwave Background (CMB) 379 000 years after ~ 3000 K
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Ramis Movassagh
c
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
So which is it?
Until a couple of decades ago, physicists thought it was the second type, because you expect gravity to slow it.
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
So which is it?
Until a couple of decades ago, physicists thought it was the second type, because you expect gravity to slow it. Recently CMB indicates asymptotically flat universe =⇒ Third type
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
So which is it?
Until a couple of decades ago, physicists thought it was the second type, because you expect gravity to slow it. Recently CMB indicates asymptotically flat universe =⇒ Third type Even more recent, we see that the expansion is accelerating =⇒ NONE OF THE FRIEDMAN solutions !
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
How far can this be pushed?
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
How far can this be pushed? As far as physics
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
How far can this be pushed? As far as physics Planck time ∼ 10−44 sec.
Ramis Movassagh
Status of Time in Physics
Time in Science and the Arrow of Time Einstein’s Relativity and Consequences Quantum Theory of Fields and the Fabric of Space and Time
Technological limitations
Factors influencing the accuracy ●
●
●
Thermal fluctuations can pollute the photonic pure tone ● Shielding of the cavity Motion of the atoms ● Better cooling techniques: ion traps, laser cooling, etc. Impurities in the cavity
Ramis Movassagh
Status of Time in Physics