As a high school student, the study of physics generally meant the
study of classical physics. To me, the idea of “Quantum physics” was just
theoretical physics that involved exploring subatomic particles. Although
quantum physics does involve inspecting the behavior and interaction of small
particles such as protons, neutron, electrons and even gluon and quarks, the
field of quantum physics is much vaster and is used to explain many unanswered
mysteries in history. The study of quantum physics reflects lights of
possibilities on ideas that may have been just fictions in the past. Quantum
physics brings the universe together; as the great physicist Erwin Schrodinger
famously said,
“Quantum
physics thus reveals a basic oneness in the universe.”
History tells many stories about the famous debate amongst
physicist that argued light to be a particle or a wave and classical physics
resolved this conflict by saying that light only behaved like a wave. It was
not until the 20th century when theoretical physicists Max
Planck proposed a new idea that proved both sides of the debate wrong. He
explained that light was not a particle or a wave but it behaved like both.
This idea of Max Plank gave birth to the world of quantum physics and many
more.
Max
Planck’s journey:
Max Planck was a young genius who was a talented pianist and very
enthusiastic about classical physics. During his time, many believed that
physics was already almost fully discovered and there were only some holes here
and there to fill in. Planck still decided to further study classical physics
just for the sake of learning and exploring.
Figure 1: Max Plank
(1858-1947)
In the beginning of 20th century, when light bulbs
started gaining massive popularity, researchers started looking for ways to
make these light bulbs more and more efficient and Max Planck was also
investigating on this issue. Classical physics assumed that as a body got
hotter, its radiation in form of light must also increase. However, closer
inspection proved this theory to be wrong or inadequate. For example, if steel
is heated, it glows in different colors according to its temperature. So, it
goes from red to yellow, till blue; but if the frequency just kept going higher
and higher with temperature, the steel at some point would radiate Ultraviolet,
which is not visible (making the steel invisible). However, this assumption of
classical physics could not be confirmed by any experiment, as the steel always
remained visible. Planck spent five years trying to explain it with classical
physics but found no satisfactory solution. In desperation, he threw out all
previous ideas and assumed instead that the radiation was not emitted continuously
but in forms of discrete packets of energy known as quanta. An analogy of this
quantization of radiation energy is water falling in droplets rather than
continuous stream. The total energy then only amounts to a multiple of his
quantum of action, a constant designated by a letter ‘h’. Overall, Planks law
stated, the radiation energy is the product of the constant h and the frequency
of the radiation (supported by experimental evidences of blackbody radiation).
Max Planck was not very confident in his new findings and theory.
He was also not comfortable denying the widely accepted concepts of classical
physics. However, this was just the beginning of a new era for modern physics
which earned him a Noble Prize and was also joined by many well-known
physicists, including: Albert Einstein, Arthur Compton, C.V. Raman, Pieter
Zeeman, Niels Bohr, Hans Geiger, Ernest Marsden and Ernest Rutherford.
Figure 2: 1927 Solvay conference in Brussels
Noble prize:
The Nobel Prize in Physics 1918 was awarded to Max
Planck "in recognition of the services he rendered to the advancement of
Physics by his discovery of energy quanta".
Modern
Quantum Physics:
The word “quantum” derives from Latin, meaning “how great” or “how
much”. The discovery of light coming in small packets of energy initiated this
field of physics. However, today it underlies the mathematical framework of
many fields of physics and chemistry, including condensed matter physics,
solid-state physics, atomic physics, molecular physics, computational physics,
computational chemistry, quantum chemistry, particle physics, nuclear
chemistry, and nuclear physics. Quantum physics traditionally investigated the
world of microscopic components. However, it is also needed to explain certain
recently investigated macroscopic systems such as superconductors, superfluids,
and large organic molecules. The world of quantum physics is wide and expanding
every day. Some fundamental aspects of the theory are still actively studied.
Broadly speaking, quantum mechanics incorporates classes of phenomena for which classical physics cannot account. For example:
Broadly speaking, quantum mechanics incorporates classes of phenomena for which classical physics cannot account. For example:
- Quantization of certain physical properties
- Quantum entanglement
- Principle of uncertainty
- Wave-Particle duality
Credits:
- https://www.youtube.com/watch?v=Ex8EvBTk9LY
- http://www.forbes.com/forbes/welcome/
- http://hyperphysics.phy-astr.gsu.edu/hbase/mod6.html
- http://roberta.tevlin.ca/
- https://www.youtube.com/watch?v=x5wlsIhooms
Photos:
- http://d3thflcq1yqzn0.cloudfront.net/000795912_prevstill.jpeg
- http://case.ntu.edu.tw/scinarrator/wordpress/wp-content/uploads/2015/05/planck_g.jpg
- http://hyperphysics.phy-astr.gsu.edu/hbase/imgmod/plnck.gif
- https://upload.wikimedia.org/wikipedia/commons/6/6e/Solvay_conference_1927.jpg
- http://spectrum.ieee.org/image/1711890