playing with ideas

I'm in my typical state of mind-not feeling too smart. About what you may wonder? First I must share the good news. It seems like my cosmological constant resolution is looking good in the eyes of the referee of my paper! I can't talk too much about this-but so far so good. But there is this other nagging thing that has occupied my mind for the past few weeks. It has to do with the Cosmic Microwave Background Radiation (CMBR) and whether or not there is parity violation present in it. To answer this question, I will have to figure out a clever way of analyzing the data which takes into account foreground noise which could also contribute to parity violation. Needless to say that I'm not an expert on analyzing the WMAP (Wilkinson Microwave Anisotropy Probe) data. So I've been trying to convince Professor Sarah Church and her Post doc Dr. Melanie Bowden to join a collaboration with me and Peskin. It will be very cool if there is parity violation on large scales. I believe that this may be a way of testing the baryon asymmetry idea I published two years ago. Time will tell...

Comments

[Dan]

Hi Stephon!

Surely, I must be misunderstanding something you say. -- So you wonder if there is a parity violation present in the CMBR. Well, if I take your question at face value, the answer is trivially "yes!". Remember that at large distances parity is *manifestly* broken spontaneously. To see this, it suffices to notices that China and the European Union aren't identical ;)). With this in mind, you can't avoid the conclusion that the CMBR, which is much larger than earth, can't help but reflect this spontaneous breakdown of parity.

Even at much smaller distances the answer is still the same. Just remember the famous Cobalt 60 experiment.

So I guess what you really mean is, does the CMBR say something about parity at length scales comparable to the wavelength of the microwaves, which are yet much smaller. This is a much more interesting question, but is there any hope of finding a productive answer? All we know about the CMBR is its large scale structure and its mostly thermal nature. Thus, if you are able to answer the question, you'd be the first physicist to find experimental signatures of UV/IR mixing. That, in turn, would automatically make you one of my personal heroes and I'm sure some people in Stockholm, Sweden, would agreee.

Best wishes,
Dan

[stephon]

Dan, you got it! If there is parity violation in the CMB at large scales then according to the Inflationary mechanism, this would suggest a UV/IR mixing. Keep up the sharp thinking.

As for China and the U.S. parity is spontaneously broken by a certain party ;)

[Koushik Dutta]

Hi Stephon,
to get some information from CMB about parity violation on large scale, essentially you have to look at the B mode polarization! But note that observed power spectra is mentioned for "BB" mode. Somehow you have to extract information for C_{TB} or C_{EB} modes from spehrical harmonics coefficients. But I guess that would be extremly small! Anyway, best of luck....
best,
Koushik

[Paul Valletta]

Stephon quote:To answer this question, I will have to figure out a clever way of analyzing the data which takes into account foreground noise which could also contribute to parity violation.

If I may?..the clever way is to seperate Expansive Modes and Contractive Modes of Thermal signiture contained within WMAP.

The cool spots must be Contractive, being part of the background radiation that has collapsed from Hot big-bang. Any thermal signitures that can be confirmed to be fluctuating, for instance any back-to-back Electro-Magnetic scattering can be slotted into Expansive Mode, thereby be contributing to a local thermal increase.

If one has a single Cosmological Constant, one emerging from a Hot Big Bang, then there are difficulties that cannot be resolved, but when one starts to assign Two Cosmological Constants ie from Hot>>Cold(contractive) and one from Cold>>Hot (expansive)..then the WMAP ,CMBR will have 'TWO' parity violations, left-handed can go either Hot>>Cold or Cold>>Hot.

One has to identify Hot backgrounds expanding 'within' Cold Contracting Backgounds. Thermometers go up as well as down!

[Hossein Yavartanoo]

Hi stephon, nice to find your interesting weblog.