Sunday, January 14, 2018

Table-Top Elementary Particle Experiment

I love reading articles like this one, where it shows that one can do quite useful research in elementary particles using experimental setup that is significantly smaller (and cheaper) than large particle colliders.

Now, he’s suddenly moving from the fringes of physics to the limelight. Northwestern University in Evanston, Illinois, is about to open a first-of-its-kind research institute dedicated to just his sort of small-scale particle physics, and Gabrielse will be its founding director.

The move signals a shift in the search for new physics. Researchers have dreamed of finding subatomic particles that could help them to solve some of the thorniest remaining problems in physics. But six years’ worth of LHC data have failed to produce a definitive detection of anything unexpected.

More physicists are moving in Gabrielse’s direction, with modest set-ups that can fit in standard university laboratories. Instead of brute-force methods such as smashing particles, these low-energy experimentalists use precision techniques to look for extraordinarily subtle deviations in some of nature’s most fundamental parameters. The slightest discrepancy could point the way to the field’s future. 

Again, I salute very much this type of endeavor, but I dislike the tone of the title of the article, and I'll tell you why.

In science, and especially physics, there is seldom something that has been verified, found, or discovered using just ONE experimental technique or detection method. For example, in the discovery of the Top quark, both CDF and D0 detectors at Fermilab had to agree. In the discovery of the Higgs, both ATLAS and CMS had to agree. In trying to show that something is a superconductor, you not only measure the resistivity, but also magnetic susceptibility.

In other words, you require many different types of verification, and the more the better or the more convincing it becomes.

While these table-top experiments are very ingenious, they will NOT replace the big colliders. No one in their right mind will tell CERN to "step aside", other than the author of this article. There are discoveries or parameters of elementary particles that these table-top experiments can study more efficiently than the LHC, but there are also plenty of the parameter phase space that the LHC can probe that can't be easily reached by these table-top experiments. They all are complimenting each other!

People who don't know any better, or don't know the intricacies of how experiments are done or how knowledge is gathered, will get the impression that because of these table-top experiments, facilities like the LHC will no longer be needed. I hate to think that this is the "take-home" message that many people will get.

Zz.

Thursday, January 11, 2018

How Do We Know Blackholes Exist?

If you don't care to read in detail on the physics, and have the attention span of a 2-year old, this is Minute Physics's attempt at convincing you that blackholes exist.



Zz.

Friday, January 05, 2018

Why Did Matter Matter?

Ethan Siegel has yet another nice article. This time, he tackles on why we have an abundant of matter in our universe, but hardly any antimatter, when all our physics seems to indicate that there should be equal amount of both, or simply a universe filled with no matter.

I have highlighted a number of CP-violation experiments on here, which is something mentioned in the article. But it is nice to have a layman-type summary of the baryo-lepton-genesis ideas that are floating out there.

Zz.

Thursday, January 04, 2018

Determining The Hubble Constant

Ethan Siegel has a nice article on the pitfalls in determining one of the most important constants in our universe, the Hubble constant. The article describes why this constant is so important, and all the ramifications that come from it.

As you read this, notice all the "background knowledge" that one must have to be able to know how well certain things are known, and what are the assumptions and uncertainties in each of the methods and values that we use. All of these need to be known, and people using them must be aware of them.

Compare that to the decision we make everyday on things we accept in social policies and politics.

Zz.

Monday, January 01, 2018

Gravitational and Inertial Mass

In this video, Don Lincoln tackles the concept of gravitational and inertial mass, and talks about the wider, more general implication of them being the same within Einstein's General Relativity.



Zz.