# Presentation: 379877

## Space, Time, and Einstein

**Francis Granger Middle School**
**Ming-Jer Wang**
-  Fermilab
**23-April-2007**

- "Space,Time & Einstein", Dr.M.J. Wang

## About Myself 

- Ming-Jer Wang
- A Visiting Scientist at Fermilab
- Experience: Fermilab, Los Alamos National Lab in New Mexico, Saclay in France, SSC Lab in Texas
- Discovery: Made contributions to the top quark discovery at Fermilab in 1995

- "Space,Time & Einstein", Dr.M.J. Wang

## Fermilab 

- "Space,Time & Einstein", Dr.M.J. Wang

##  Why do we choose this Topic – “Space & Time”?

**It is related to the researches at Fermilab**
**It is related to what you are learning about –**
**Physics**
**Chemistry**
**Astronomy **
**An exciting subject!**
**How do you learn about the stars?**
**What do you learn about the stars?**
**Where?  -> “Space”**
**When?   -> “Time”**

- "Space,Time & Einstein", Dr.M.J. Wang

##  Why do we choose this Topic – “Einstein” ?

**1905: Clerk in Patent Office**

**At older age****!**

**School**** ****boy**

- "Space,Time & Einstein", Dr.M.J. Wang

## Einstein's Three Great Discoveries

**1. ****He verified the existence of “atoms” by explaining the zig-zag motion of pollen grains in water, noticed 80 years earlier.**
**2.  ****He proved that light could be understood as little “bullets” of energy (or particles).**
**3.  ****He developed the ****theory of relativity****, in which “moving” observers disagree about simple measurements like time and distance****.**
**Discovery #3 ****is what we are going to talk about today!**

- "Space,Time & Einstein", Dr.M.J. Wang

##  Space and Time in Ordinary Life

**Space**
**Traveling route**
**Go to school **
**Go home **
**Go shopping**
**Demo - rulers**
**Time**
**Daily schedule**
**Meal time **
**School time **
**Bed time **
**Demo - clocks**

- "Space,Time & Einstein", Dr.M.J. Wang

##  Concept History of Space 

- "Space,Time & Einstein", Dr.M.J. Wang

##  Concept History of Space 

- "Space,Time & Einstein", Dr.M.J. Wang

##  Concept History of Time

| the definition of absolute time:
 “Absolute, true, and mathematical time, of itself and from its own  
nature, flows equally without relation to anything external” |
| --- |

**Newton’s view **

- "Space,Time & Einstein", Dr.M.J. Wang

##  Concept History of Time

**Einstein****’s challenge**

**Change ****the definition of time****:**
**  “****It might appear possible to overcome all the difficulties attending ****the definition of ’time’**** by substituting ‘the position of the small hand of my watch’ for ‘time’ “.**
**Example:**
**“ ’****That train arrives here at 7 o’clock,’ I mean something like this ‘The pointing of the small hand of my watch to 7 and the arrival of the train are simultaneous events’ ”**
**              ****of the 1905 paper by Einstein **

- "Space,Time & Einstein", Dr.M.J. Wang

## Simultaneity is Relative! 

- "Space,Time & Einstein", Dr.M.J. Wang

## Moving Train seems to be Shorter !

- "Space,Time & Einstein", Dr.M.J. Wang

##  Moving Clock Seems to be Slower !

- "Space,Time & Einstein", Dr.M.J. Wang

##  Effects on Space & Time

- “The speed of light is the same for everyone” & this gives unintended results
- From your point of view, the moving things seem:
- Shorter in space
- Slower in time
- But the speeds have to be very big to make such difference!
- You can go faster & faster but never ever reach the speed of light

- "Space,Time & Einstein", Dr.M.J. Wang

## Fermilab’s  Accelerator pushes protons to:0.9999995 x (speed of light)(This is about 186,000 miles per second!)

**4 MILES**

**Every second, they go around the 4-mile ring about 50,000 times!**

**The protons:**
** ****Seem 1000 times thinner.**
** ****Have clocks that run 1000**
**  ****times slower.**

- "Space,Time & Einstein", Dr.M.J. Wang

## Space & Time are bent, or curved by matter

- "Space,Time & Einstein", Dr.M.J. Wang

## Light path is bent, or curved by matter

| The position of star observed during eclipse confirmed Einstein’s theory |
| --- |

- "Space,Time & Einstein", Dr.M.J. Wang

## A way to study starts beside space & time – “Spectral Lines” 

- "Space,Time & Einstein", Dr.M.J. Wang

## Two way to detect star relative motion – Red Shift & Blue Shift

- www.astro.ucla.edu/%7Ewright/doppler.htm

**(Object moving ****away****)**

**(Object**** ****moving toward)**

- "Space,Time & Einstein", Dr.M.J. Wang

## An Expanding Universe

- A *tiny* spot from the **Hubble Space Telescope**
**Every blob is a galaxy** with ~**100,000,000,000 stars****.**

**All are rushing away from us,**
**RED**** ****SHIFT**** ****. . .  expanding Universe!**
**Dr. Hubble (Wheaton) discovered that****.**

***BIG BANG***
- 13.5 billion years ago
- But not **BIG**, **TINY**!

- "Space,Time & Einstein", Dr.M.J. Wang

## Final Life of Big Stars – Black Holes

**The Black Hole is invisible,**
**but you can see stuff around it.**

- "Space,Time & Einstein", Dr.M.J. Wang

## Discovery:  Evidences of Black Holes

**Hubble Uncovers Dust Disk Around a Massive Black Hole**

- "Space,Time & Einstein", Dr.M.J. Wang

## Summary of What We Have Learnt

- Space & Time are relative
- Moving things look shorter & slower
- Spacetime is bent by matter
- Light path is bent by matter
- Spectral lines are used to identify chemical elements on stars
- Red shift & blue shift of spectral lines are used to detect relative motions of stars
- The present universe is expanding
- If you want to learn more ->

- "Space,Time & Einstein", Dr.M.J. Wang

## Welcome to Fermilab !!!

- Come to visit Fermilab – A place to explore nature at the smallest scales !!!
- Come to Lederman Science Center ( lots of science demonstrations & fun !!! )
- Come Ask-a-Scientist
- Come for the Prairie

- "Space,Time & Einstein", Dr.M.J. Wang