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Showing posts with label Light. Show all posts
Showing posts with label Light. Show all posts

Friday, 29 November 2013

HOW ORDERED IS TIME?

Time...
(Source: www.ocvote.com, 2013)
Everyone, on default, just start thinking that time is always rigid and will keep moving forward at a constant rate like a uniformly speeding bullet in space. But how true is this?

It's no news again, since special relativity arrived, that time can actually do the following;

1. Slow down (with increase in speed as seen in rockets),
2. Speed up (with increase in altitude as seen in satellites),
3. And come to a halt (when gravity gets as high as infinity as theorized in black holes).

  • But how 'ordered' is time?
  • Can time go back?

ANSWER 1:

Let's take a look at something that happens in the DOUBLE SLIT EXPERIMENT as an example.

First, i have to describe this experiment for everyone to understand.

Title: DOUBLE SLIT EXPERIMENT
Aim: To study the behavior of photons as they travel from one end of a tube to the other.
Description:
1.The Tube used in this experiment has a light source at one end, and a camera at the other end.
2.Between the Light source and the camera, a flat boundary is inserted that has two straight and parallel openings (or slits) through which the photon should pass through.
3.Single photons of light will be shot from the light source to pass through the slits and arrive at the camera.


During the experiment,
-A boundary with just one slit was first used.
RESULT: the photons were observed to pass through the single slit and arrive at the camera randomly - this is normal.

-The experiment was now done again. This time, the boundary with just one slit was now removed and replaced with the one that has a double slit.

EXPECTATION: was that each photon should pass through one of the slits and arrive randomly like normal.

Expected Result
(Source: www.mysearch.org.uk, 2013)
But this was not the result. Read on;

RESULT: an interference pattern was seen on the screen.

Fringes occurs on screen.
This result implies that,
1.each photon interfered with themselves, and
2.passed through both slits at the same time.


THIS MEANS THAT DURING THIS EXPERIMENT, EACH PHOTON ACTUALLY EXISTED AT TWO DIFFERENT PLACES AND AT TWO DIFFERENT TIMES.


That is, time fragmented or separated.
So I ask, How ordered do you think that time is here? was it actually moving uniformly forward? Answer!


ANSWER 2:
Also, it has been proved one paper that time can move backwards with the help of WORMHOLES.

A Wormhole

Wormholes are tiny passage between universe. Manipulating them to get a time tunnel in which both ends exists at two different places with different time is very theoretically possible. In other words, time travelling backwards here, is theoretically possible.

Don't fail to drop your questions and comments.
A very big thanks to Dr. Michio Kaku for his Video on TIME.
Enjoy!

Thursday, 14 November 2013

WAVE PARTICLE DUALITY OF LIGHT: SUMMARISED - PART ONE

Source: commons.wikimedia.org

Light is undoubtedly a type of wave and at the same time, it still exhibits properties that only a particle would exhibit. Now the issue is why?


First lets discuss on what properties makes light a wave.



LIGHT AS A WAVE

Light is a wave, it exhibits all the known properties of waves. From the first to the fifth. Now let us take a quick view through all of these wave-like properties and see the cases where light exhibits them...

1. Refection
probably the most common and explains how we see our images in a mirror.

2. Refraction
the bending of light rays. It explains why a light bends when it changes medium; why a straw appears broken in a clear glass of water and even extends to apparent depth.

3. Interference:
When two identical waves meet in the same medium, they interact with each other in order to strengthen themselves(Constructive) or to destroy(destructive) themselves. This exhibits this too like other waves.

4. Diffraction

Single slit Diffraction of Light
(Source: cronodon.com, 2013. Image was also edited)

Diffraction is the bending of waves when they pass through an opening lower than their wavelength. This is applicable in reading a CD or DVD disc.
Read more on interference and Diffraction here.


5.Polarization
Polarization is the change in the plan of oscillation of light waves. Its occurrence in nature makes the sky appear blue and is used in many other fields.

Light isn't just a wave, it has a family called ELECTROMAGNETIC WAVES it has all their properties. From their common velocity (c= 2.997 x 10^8m/s) to a perfect place in their frequency(400-790THz) and wavelength(380-750nm) spectrum.

Light in the Electromagnetic Spectrum
Source: www.itseducation.asia


LIGHT AS A PARTICLE

Wow, now light is a particle too. It has properties that only particles would exhibit.

1. Light supports the view that its is a stream of particles called PHOTONS.
This was postulated by Albert Einstein. Photons are the smallest unit of radiant energy. They are like small particles that makes up light waves.
-The greater the number of photons, the greater the intensity of light.
-The higher the frequency of oscillation of the photons, the more energy they carry.
This energy is given as E=hf;
where, E = Energy of oscillation of photon
h = Planck's constant (6.63 × 10^-34 m2kg/s)
f = frequency of oscillation.

2.It obeys the law of conservation of momentum, in fact, it can knock off other 'particles' and transfer energy to them.
This is seen in an phenomenon known as the Compton effect.

The Compton Effect

Source: whs.wsd.wednet.edu

This is seen in cases where light rays are used to liberate electrons from the surface of metals (Read Photo Electric Effect). It is noticed that the energy the electrons, leaving the surface of the metal possesses, approximately equal to the energy of the colliding photon. This means that, the laws of conservation of momentum and energy has been obeyed.


Continue to WAVE PARTICLE DUALITY OF LIGHT: SUMMARIZED - PART TWO