Frb

Fast radio bursts are short flashes of radio emissions that are picked up on Earth, and whose source has never been identified. They were first picked up in 2007, and scientists have only detected fewer than two dozen of them since – but have noticed strange, apparently organised, patterns in how they are found.

Professor Loeb along with Harvard's Manasvi Lingam have explored whether those strange messages could be coming from a huge radio transmitter that is so powerful that it could throw its messages across the galaxy. They found that it would be possible build such a transmitter – if it were solar powered, it would need the sunlight falling on an area of a planet twice the size of Earth to generate enough energy.

Such a technology is far beyond what we could ever hope to build today, the scientists note. But it is not beyond the law of physics, or out of the reach of a very developed alien civilisation.

---

Fast radio bursts may be a natural astrophysical phenomenon. It's interesting, though, that 8 of 20 I've seen listed at Wikipedia have dispersion values very close to small integer multiples of the value of 187.5 cm-3/pc . Hard to see how a natural phenomenon could arrange that.

They were first picked up in 2007, and scientists have only detected fewer than two dozen of them since –

Just 24 in 10 years is not a lot to be particularly fussed about is it?

Given the size of the universe that sounds huge to me.

---

Looking for further order in the dispersion values of fast radio bursts, found the following:

Four additional FRBs have quite similar values, 723 to 790 cm-3/pc , which are all very close to four times the base value previously reported-- 187.5 cm-3/pc .

Listing all of the orderly values:

746=~ 4 x187.5

375= ~ 2 x 187.5

944.38= ~ 5 x " "

553.3 = ~ 3 x " "

557= ~3 x " "

952.4= ~5 " "

562.7= ~3 x " "

559= ~ 3 x " "

790= 1.053 x750

723=.964 x 750

779= 1.038 x 750

776.2 =1.034 x 750

Below find a link to the Wikipedia article on fast radio bursts, in which the dispersion values were found in a table--' list of bursts':

https://en.wikipedia.org/wiki/Fast_radio_burst

What is the unit cm-3/pc ; and what was the content of these fast radio bursts ? Do they contain any modulation ? What part of the sky do we think they are coming from ?

The unit cm-3/pc is used to measure of the amount of apparent dispersion in wavelength suffered by radio waves after they have traveled long distances through space . It amounts to one thousandth of a centimeter of wavelength per parsec's distance through space (3.26 light years).

It's been suggested that certain forms of modulation could appear to be such dispersion. Such modulation could explain the small integer multiples of of the base value of dispersion, 187.5 cm-3/pc.

Fast radio bursts appear to come from various parts of the sky. These are very broadbanded and very powerful radio emissions, which appear to be emitted from quite small sources. You may find further details in the article linked in my previous post.