Status of Time in Physics

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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?

[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

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.

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 F = m a = m x “law of motion”

Physics (empirical) Math (differential equation)

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

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

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:

● S. Carroll's talks and book ● Schrödinger, 'what is life?' ● H Price, Time Arrow (Phil.)

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

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 Arrow of time

Many ways of having such evolution t t > t 0 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 Arrow of time

t > t t 0 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 Arrow of time

YES!

“...You would have to wait a long time”

- L. Boltzmann

NOT Many ways of having such evolution t > t t 0 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 Micro vs. Macro States

Microstates: any particular conﬁguration in the phase space Macrostate: sets of macroscopically indistiguishable microstates S = kB lnD 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

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 lnD

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 lnD 1 S = k ln = −k lnD drawn B D B 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

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

Complexity

M 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 Quantum theory Preserves Causality, Determinism, ... 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

Einstein's relativity Quantum theory Preserves Causality, Determinism, ... Inherently probabilistic, Heisenberg's uncertainty 1 principle, …. 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:

● S. Hawking, Briefer History of Time ● W. Rindler, 'Relativity' ● 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 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

! elative - ق

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 = mc2

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 E = mc2 ⇔ m = 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

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

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 ! 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 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 = mc2 1 ∆E ∼ ∆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 = mc2 ⇔ m = c2 1 ∆E ∼ ∆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+

1 Δ E ~ Δ 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: It's kinda of exciting?

e+ p+ e- k+ k- μ+

μ- ~ 10 -13 – 10 -16

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.

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 5.39121 × 10−44 s Planck mass 2.17645 × 10−8 kg Planck length (ℓP) 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 E = m c2

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.

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

-120 Λobserved ~ 10 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”? ? J us T t h he a re pp ! en Believe it or not you do fine tuning : s t o be

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 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

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

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 ± δ 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 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 ± δE E E

Feed back To Drive the cavity

~ E E E

Feed back To Drive the cavity

~ E E E

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 1,121,015,393,207,857.4(7) Hz

3 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

- Wikipedia

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

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 + Thank youi }. 2

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

379 000 years after ~ 3000 K

c c

c c c

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.

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