Where do we come from?
Perspectives from Physics
Hitoshi Murayama (Berkeley, Kavli IPMU Tokyo)
ISCO2023, OIST, Feb 27, 2023
東京大学
シンボルマーク+ロゴタイプ
新東大ブルー

基本形

Director of the Kavli Institute for the Physics
and Mathematics of the Universe

huge responsibility!

Director of the Universe

Not high enoughauthority
Voice of God

Director of the Universe

From space telescope to 4D microscope

Tad Takahashi

Shigehiro Nagataki
Gordon Baym

Ultra High Resolution & Multi Probe in-vivo Analysis
Drug A

RI Probes

Drug B

Gamma-ray

Radio isotope (RI)

Tumor©Kavli IPMU

We physicists askvery basic questions
How did the Universe begin?
What is its fate?
What is it made of?
What are its basic laws?
Why do we exist?
Where do we come from?

Where do we come from?

Credit: Reuters
http://www.kamakura-burabura.com/meisyokamakuradaibutu.htm
Credit: John Shiron 2011

Religions
https://snaplace.jp/金閣寺（鹿苑寺）/

https://commons.wikimedia.org/wiki/File:Sultan_Ahmed_Mosque.jpg

Where do we come from?

https://www.metmuseum.org/art/collection/search/191811

Philosophy

Where do we come from?

Evolutionary biology

Time machines

Credit: NAOJ

Credit: CERNAndromeda
2.3 million light years

HSC team
Subarutelescopecluster of galaxies
2.1 billion light years

Credit: NASAAbell 2218

James Webb Space Telescopegalaxy @ 13.5 billion light years
Credit: NASA

Expanding Universe• Einstein: Universe is not just abox

• It can bend, twist, stretch, andcollapse• Universe itself can become
bigger• Gets colder and colder• It must have been small and hot• Big Bang !

We can see the Big Bang!

Credit: UC Berkeley

Credit: NASAWe can seethe Big Bang!

13.8 billion lyrs away
= 13.8 billion years ago

Credit: NASAPARTICLE

Credit: ESA

in3m

２ニュートリノ
陽子
Barbara JacakPARTICLE

２陽電子
ヘリウム
telescopes

２ニュートリノ
陽子

Big Bang leads to H:He ~ 3:1２陽電子
ヘリウム
agrees with observation!
particle accelerators

Credit: Particle Data GroupParticles

The Universe

SmallerBigger
Island EarthAtoms

HumanMedicine

The smallest = elementary particles
meets
The biggest = the Universe

dark matterdark energy

The Universe

Credit: DOE/NSF Quantum Universe

atoms

Dark Mattera hundred billion
stars

solar system revolves at 220 km/s
what is pulling us inside?

28,000 lyrs

true nature of galaxies
100k lyrs
stars

dark matter>M lyrs

cluster of galaxies

Credit: NASA

Abell 2218
2.1B lyrs

Credit: NASA/ESA

Credit: LSST

Credit: Masahiro Takada

image invisible
dark matter

more than 80% of matter in the Universe is not atoms

Credit: Naoki Yoshida

10–5

Dark Matter is our Mom

without dark matterwith dark matter

250 million
light years

250 million
light years

3D maps

1billionlightyeytsraearsnolliib
8

Dark matterhgli

1billionlightyearsb8Galaxies

iglnthsraeyoilil

Credit: Subaru HSC collaboration

Shiro Ikeda

Event Horizon Telescope team

weighs only 4 million times the Sun

Credit: ESO

http://www.eso.org/public/outreach/press-rel/pr-2008/phot-46-08.html

What is dark matter?
• Not black holes• except for ~nm size
Alex Kusenko• Not dim stars• Not neutrinos• Nothing we know of• New particles?
Credit: DOE/NSF Quantum Universe

WIMPs• It may be WIMP (WeaklyInteracting Massive Particle)• Stable heavy point-like particle
produced in early Universe• millions of them going through ourbody every second

Credit: NASALHC
Redo the Big Bang!

Credit: CERN

Credit: CERNATLAS detector

Credit: CERN

Credit: CERNCan we make dark matter?
E=mc2

accelerator=microscope• can’t see things smaller thanthe wavelength• short wavelength=high energy

hc=E

Also PET
Radiation therapy

Or SIMP?

Yonit Hochberg

•Perhaps dark matter is notelementary but composite?

• Then it has a nite sizeattens
thespikesindark•matter density pro lefi•

actually desirable for dwarf
galaxies?

fi

flsize mattersin3m

２ニュートリノ陽子
In ationdark matter

２陽電子
ヘリウム
telescopes

２ニュートリノ
陽子

Tom MeliaflCredit: Particle Data Group

２陽電子
ヘリウム
Big Bang leads to H:He ~ 3:1
agrees with observation!

fl

In ation

Misao Sasaki

Credit: ESA

Quantum uctuationsflhttp://www.youtube.com/watch?v=uxlOMa6pdr4

fl

In ation is our Dad

in3m

２ニュートリノ
LiteBIRD

陽子
In ation

２陽電子
ヘリウム

dark mattertelescopes

２ニュートリノ
陽子

flCredit: Particle Data Group２陽電子ヘリウム

Reenacting the Big Bang with Cal Marching Band

Credit:UC Berkeley

Where do we come from?

physicists
Dark Side:In ation
Dark Matterfifl© Lukas lm

Science for Peace
And Development
2014/10/20
UN Headquarters
In New Yorkhttps://www.ipmu.jp/ja/node/2050

fiMeKoAnnan

Sep 30, 2008
Kaguya

The world can work together!