Observer Affects the Objects – It happened first time in the history of physics that certainty of physical laws has changed into the laws of uncertainty. It’s very self canceling term ever used in the world of science, “the law of uncertainty”. As we knew that physics is the knowledge of certain principles. It deals with certain measurements, certain quantities, certain rules, certain objects and certain levels. Physics never believed in such things like uncertainty principle before quantum mechanics.
It’s much amazing and unbelievable, what does an observer do with material of the world and why? Observer maybe a human being, animal, camera or some other observing device but it still stands very astonishing to physicists that an observer can affect the material at least on its sub-atomic level.
If you know little about the physics you’ve been definitely reading the double slit experiment. Before I go ahead I want to explain the double slit experiment for those who don’t know about it.
Double Slit Experiment
Double slit experiment explains the behavior of waves and particles. See the image below,
We know, when we shoot particles at full atomic or molecular level from double slit they make a pattern of only two bands as shown in the below image,
As well as when we send the waves of water through a double slit, what happens? They make an interference pattern between themselves and create several light bands as the below image,
But what happens when we shoot particles at sub-atomic level through a double slit? That is the most amazing question of today’s physics. When we shoot electrons through a double slit they behave like waves rather than the particles. See again an image,
All things that I mentioned above are already known and understood by physicists but one thing remains undefined that undermines all of the rules and laws of physics in just blinking the eyes of observer and that is very, very strange to the science till today. What’s that?
Let’s talk a little about that magic called “the decision power of electrons”. What an amazing phenomenon is it? Electron decides (in some words) to act differently when some observer is observing it. How can this amazing phenomenon be a scientific thing?
How Observer Affects the Objects?
When an observer is observing the behavior of sub-atomic particles they change their behavior. In double slit experiment they behave like particles when an eye or a measurement device is watching them, while they behave like waves when observer is not there.
Due to this uncertainty of sub-atomic particles behavior, the law of uncertainty comes into the certain world of physical objects. Thus physics begins to touch the boundaries of metaphysics. As the conclusion a physicist actually says that observer affects the objects.
Erwin Schrödinger is a famous physicist who exchanged the letters with Einstein about his thought experiment on the behavior of sub-atomic particles. In the course of which Einstein had pointed out that
The state of an unstable keg of gunpowder will, after a while, contain a superposition of both exploded and unexploded states.
Schrodinger’s cat is a thought experiment, usually described as a paradox, devised by Austrian physicist Erwin Schrodinger in 1935. It illustrates what he saw as the problem of the Copenhagen interpretation of quantum mechanics applied to everyday objects. The thought experiment presents a cat that might be alive or dead, depending on an earlier random event. In the course of developing this experiment, he coined the term Verschrankung (entanglement).
Schrodinger wrote:
One can even set up quite ridiculous cases. A cat is penned up in a steel chamber. Along with the following device (which must be secured against direct interference by the cat): in a Geiger counter, there is a tiny bit of radioactive substance. So small that perhaps in the course of the hour, one of the atoms decays. But also, with equal probability, perhaps none. If it happens, the counter tube discharges, and through a relay releases a hammer that shatters a small flask of hydrocyanic acid.
If one has left this entire system to itself for an hour. One would say that the cat still lives if meanwhile no atom has decayed. The psi-function of the entire system would express this by having in it the living and dead cat (pardon the expression) mixed or smeared out in equal parts.
It is typical of these cases that an indeterminacy originally restricted to the atomic domain becomes transformed into macroscopic indeterminacy, which can then be resolved by direct observation. That prevents us from so naively accepting as valid a “blurred model” for representing reality. In itself, it would not embody anything unclear or contradictory. There is a difference between a shaky or out-of-focus photograph and a snapshot of clouds and fog banks.
The above text is a translation of two paragraphs from a much larger original article that appeared in the German magazine Naturwissenschaften (“Natural Sciences”) in 1935.