y is it impossible 2 create perfect vacuum ??

Asked by shuchi.saumya | 16th Sep, 2010, 12:00: AM

Expert Answer:

Practically, it is impossible to make a perfect vacuum. A perfect vacuum is defined as a region in space without any particles. 

The problem is that to maintain a vacuum in a region you have to shield it from the environment. It is not difficult to make a container that would prevent atoms from entering the region. 

The first problem is that the container itself will radiate photons (which in turn can create electron positron pairs in the vacuum) if it is not kept at a temperature of 0°K. Note that a perfect vacuum has by definition a temperature of 0°K. reaching 0 °K is practically impossible. 

The second problem is that there are weakly interacting particles that could enter the region. No matter how thick the walls of the container are, there is always a finite probability that, say, a neutrino would enter the region.

Answered by  | 17th Sep, 2010, 03:05: AM

Queries asked on Sunday & after 7pm from Monday to Saturday will be answered after 12pm the next working day.