slide1
Download
Skip this Video
Download Presentation
Jae-Weon Lee* (Jungwon Univ.) Jungjai Lee (Daejin Univ.) Hyungchan Kim (Chungju Univ.)

Loading in 2 Seconds...

play fullscreen
1 / 44

Jae-Weon Lee* (Jungwon Univ.) Jungjai Lee (Daejin Univ.) Hyungchan Kim (Chungju Univ.) - PowerPoint PPT Presentation


  • 163 Views
  • Uploaded on

Gravity and dark energy from quantum information. Jae-Weon Lee* (Jungwon Univ.) Jungjai Lee (Daejin Univ.) Hyungchan Kim (Chungju Univ.). Relativity and Quantum information. Modern Physics. Quantum Mechanics. Relativity. Information.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about ' Jae-Weon Lee* (Jungwon Univ.) Jungjai Lee (Daejin Univ.) Hyungchan Kim (Chungju Univ.)' - faolan


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
slide1

Gravity and dark energy

from quantum information

Jae-Weon Lee* (Jungwon Univ.)

Jungjai Lee (Daejin Univ.)

Hyungchan Kim (Chungju Univ.)

slide2

Relativity and Quantum information

Modern Physics

Quantum

Mechanics

Relativity

Information

Quantum information and special relativity have a fundamental relation.

But there is no obvious reason for this!

two great mistakes of einstein
Two Great mistakes of Einstein

= The biggest blunder of my life!

 Dark energy

Entanglement

= Spooky action at a distance?

 Quantum information science

Two great puzzles of modern physics

Surprisingly, they are related!

slide4

Surprising relations!

Dark

energy

Entanglement

energy

Quantum

Mechanics

Gravity

Holographic

principle

Thermody

namics

Jacobson

& Verlinde

& Padmanabhan

Causal horizons

Landauer’s principle

Information

landauer s principle

Information is Physical!

Landauer’s principle
  • Erasing information dS consumes energy TdS
  • dE=TdS

(Two level system)

M. B. Plenio and V. Vitelli

quant-ph/0103108

slide6

Quantum mechanics and Information

The most elementary quantum system

represents the truth value of one proposition only (bit?). This principle is then the reason for the irreducible randomness of an individual quantum event and for quantum entanglement

Cˇ . Brukner, A. Zeilinger

It from Bit!

black hole entropy contains everything
Black hole entropy contains everything

relativity

thermodynamics

Holographic principle

Bekenstein-Hawking entropy

gravity

quantum

BH

entanglement and horizon
Entanglement and Horizon

,

Entanglement

entropy

information

A

B

If there is a causal horizon (information barrier),

it is natural to divide the system by the horizon.

conjecture
Conjecture
  • Information is fundamental
  • Holographic principle and Landauer’s principle
  • as basic principles
  • Causal (Rindler) horizons are involved with
  • information erasing

Physical Laws describe information loss

at causal horizons!

Horizon information barrier (erasing, entanglement)  dE =TdS

slide10

Dark energy from information

LLK:JCAP08(2007)005

Black hole-like universe

Landauer’s principle

Hawking temperature

Entanglement entropy

Horizon energy

Expanding

event horizon

Holographic dark energy

Information erasing

One can also think this DE as cosmic Hawking radiation!

In short, T~1/r, S~ r^2  density M_P^2 /r^2 ~ M_P^2 H^2 as observed

slide11

More general Version

Entropic force

Holographic DE

For Bekenstein-Hawking entropy

negative pressure
Negative pressure

M. Li

Freedman eq. & perfect fluid

Effective

EOS

slide13

Newscientist

Prokopec

"They\'ve come up with an interesting physical mechanism for how [virtual particles] could lead to dark energy,

They have chosen a very reasonable value for this, but if it turns out that this value is slightly wrong, it could throw

off all their predictions "

Seth Lloyd

"I think they could really be onto something,"

slide15

EOS

WMAP7

Gong et al

slide16

From QFT

But from dE=TdS

should be zero

Zero Cosmological Constant JWLee, 1003.1878

 QFT should be modified for large scale!

Cf) Curved spacetime effect

Dark energy is cosmic Hawking radiation (it has an appropriate EOS!)

our solution to dark energy problem
Our solution to dark energy problem
  • 1) Why it is so small?  Holographic principle
  • 2) Why it is not zero?  Due to quantum fluctuation
  • 3) Why now?  Inflation or r~ O(1/H)
  • 4) Zero cosmological constant
  •  Holographic principle & dE=TdS

without fine tuning

slide18

Our works so far

  • Dark energy from vacuum entanglement.JCAP 0708:005,2007.  dark energy from information
  • 2) Does information rule the quantum black hole?
  • arXiv:0709.3573 (MPLA)  Black hole mass from information
  • 3) Is dark energy from cosmic Hawking radiation?Mod.Phys.Lett.A25:257-267,2010 Dark energy is cosmic Hawking radiation
  • <Verlinde’s paper> Gravity and mechanics from entropic forcearXiv:1001.0785
  • Cai, Cao, Ohta. Friedmann eq.
  • Easson, Frampton, Smoot entropic dark energy & inflation
  • Gravity from Quantum Information.1001.5445 [hep-th] (suggested in 2009)
  • Gravity as Quantum Entanglement Force. arXiv:1002.4568 [hep-th]
  • Zero Cosmological Constant and Nonzero Dark Energy from Holographic Principle.arXiv:1003.1878
  • On the Origin of Entropic Gravity and Inertia.arXiv:1003.4464 [hep-th]
  • Deriving Verlinde’s theory from quantum information model
  • 5) Quantum mechanics emerges from information theory applied to causal horizons  arXiv: today
slide19

Verlinde’s Idea 1: Newton’s equation

arXiv:1001.0785

Entropic

force

But strange assumption??

Holographic screen

slide20

Verlinde’s Idea 2: Newton’s gravity

# of bits

,Holographic

, Equipartition

, Newton’s gravity

Verlinde’s holographic energy is very similar to our entanglement energy!

slide22

Einstein Equation

Information erasing

Generalizing

a la Jacobson

where

using Raychaudhuri eq.

using Bianchi identity

Einstein eq. represents information erasing for Rindler observers!

slide23

Verlinde’s entropic force from information theory

J.Lee arXiv:1003.4464

Verlinde’s entropy!

Verlinde’s theory is recovered from information theory.

slide24

QFT from information

JWLee hep-th today

Rindler observer has no information about field or paths

in the F wedge  Quantum Randomness

 No “objective physical reality”

slide25

QFT from information

Energy conservation

constraint

Maximize

Shannon entropy

Boltzmann distribution

Rindler shows

Quantum partition function

slide26

Conclusions

  • 1. Landauer’s principle, dE=TdS
  •  Information is thermal Energy
  • 2. Energy is Mass (matter)
  • 3. Einstein Equation G=M
  • Matter generates Gravity
  • 4. Unruh effect  Quantum is thermal

1+2= Matter is information,

1+2+3= Gravity is information!

1+4= Quantum is information

slide29

Conclusions

  • Landauer’s principle  1st law of thermodynamics
  •  Jacobson’s idea (Gravity=Thermodynamics)
  • General relativity
  • dark energy
  • + some hints on arrow of time and
  • origin of quantum mechanics?
slide30

Gravity as Quantum Entanglement Force.Jae-Weon Lee, Hyeong-Chan Kim, Jungjai Lee

arXiv:1002.4568

Arrow of time

Entanglement force

merits of our theory
Merits of our theory
  • simple
  • links information to gravity
  • calculable
  • explain dark energy, black hole mass
  • & BH information paradox (hopefully)
  • gives some hints on the holographic principle
slide32

Schrödinger’s cat

Environment

정보가 새어나감

|Dead>+|Alive> pure state

entanglement

Decoherence

실제

State=|Dead>|Env0>+|Alive>|Env1>

 Tracing Env

 Dear or Alive, density matrix=|Dead><Dead|+|Alive><Alive|

 Classical world

holographic principle
Holographic principle
  • All of information in a volume can be described by physics
  • on its boundary.
  • The maximum entropy within the volume is proportional to
  • its Area.

R

QFT over-counts

independent d.o.f. inside

a boundary!

Whole new physics!

vanrenesse-consulting.

Scientific American August 2003

slide34

Entanglement

Nonlocal quantum correlation

|Dead>|Env0>+|Alive>|Env1>

Subluminal

signaling

Superluminal

signaling?

Measurement |Env0> or |Env1>

Quantum mechanics somehow protects superluminal communications

even though it has a NONLOCAL correlation!

slide35

Black hole and Entanglement

|Env>

|Dead>|Env0>+|Alive>|Env1> possible?

Quantum vacuum fluctuation allows entanglement between

inside and outside of the horizon due to the uncertainty problem.

Hawking radiation

how to calculate entanglement entropy

R

How to calculate Entanglement entropy
  • Hamiltonian

Srednicki,PRL71,666

,

  • Vacuum
  • Reduced density matrix

Eigenvalues

  • entropy

Calculable!

li s idea

L=

L=

L=

L=

Li’s idea

H

Let\'s use instead of

R

t

time ~

is consistent with SNIa,CMB,SDSS,BAO.

  • Ok. It seems to work now, But
  • Why this form?
  • Why instead of ?
  • Why d ~1?

Our work answers to

these questions

the cosmological constant problem in detail

Sum of all oscillators

Zero point Energy

The Cosmological constant problem in detail

= Huge sum of harmonic oscillators

Quantum field=

UV cutoff a ~1/Mp

L IR cutoff

  • Naive expectation
  • Observed

But

where does negative pressure come from
Where does negative pressure come from?

perfect fluid

1st-law

If energy increases as the universe expands, this matter has a

negative pressure

is an increasing function of t

P < 0

slide41

Quantum mechanics and Information

The most elementary quantum system

represents the truth value of one proposition only (bit?). This principle is then the reason for the irreducible randomness of an individual quantum event and for quantum entanglement

Cˇ . Brukner, A. Zeilinger

It from Bit!

the cosmic coincidence problem
The Cosmic coincidence problem
  • Observed

for

If we think this is an accidental coincidence

Cosmic coincidence problem

If we believe there is a hidden law behind this

Holographic dark energy models

  • 1) Why it is so small? Holographic principle
  • 2) Why it is not zero? Entanglement energy
  • 3) Why now? Cosmic coincidence problem

( QFT over-counts modes!)

( There is always quantum fluctuation!)

problem

(We need an inflation!)

slide43

Holography and Entanglement

  • Entanglement is
  • Area Law (in general)
  • Nonlocal
  • Related to Horizons
  • Fundamental
  • Observer dependent
  • Very fast decoherence
  • Information erasing!

It reminds us of the Holographic principle!

ad