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Inaction in Syria is Unconscionable

There are those events in history that define evil, they stain our conscience long after they've past, Bosnia, Rwanda, Halabja, and now, Syria.

To all but the most committed conspiracy theorists, Assad is guilty. Activists from the Violations Documentation Center (VDC) reported two separate attacks involving the use of chemical weapons in the Eastern Ghouta region. Independently, the Union of Medical Care and Relief Organizations also received reports of two separate incidents and we know from both the Syria Civil Defence and the Syrian American Medical Society that those hundreds exposed to the attack were brought to medical facilities where they showed symptoms consistent with exposure to a chemical agent. 

That in addition to the blood and urine samples, there's hardly any room for serious doubt over what happened, large compressed gas cylinders were used in the attack, of the same type used in previous aerial raids. Aircraft spotters reportedMi-8 Hip helicopters in the area…
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The 'Inflation Debate' in Cosmology Continues

Last year Scientific American published a controversial article titled "Pop goes the Universe", the three authors Anna Ljjas, Paul Steinhardt and Abraham Leob are skeptics of inflationary cosmology and they gave their reasons why. That was followed with a letter signed by 33 physicists who study cosmology, denouncing the article that had been published.

Originally I didn't even want to comment, the whole business of signing a letter calling for a retraction instead of writing to the editor rubs me the wrong way. It reminds me when a hundred Nazi scientists were called on to denounce Einstein, if he were wrong you'd only have needed one. Science media should be an open space where people are allowed to hear about controversies in physics. Inflation is not a well established scientific theory like the Big Bang or evolution, and some very highly respected theoretical physicists are in real doubt.

Inflation probably is the correct theory, it's the best worked out mo…

Is Quantum Cosmology Serious Physics?

Alexander Vilenkin, one of the major contributors to the field.

Quantum cosmology is in an incredibly infantile and esoteric branch of theoretical physics; with a whole series of practical and conceptual problems. Chris Isham says because of these, no one is really sure whether quantum cosmology is even a valid branch of science, or whether the whole project is just misconceived.

The unique claim of quantum cosmology isn't just that quantum theory applies to things within the universe but to the universe itself, particularly when the universe was small enough at the Big Bang.

The first and third most popular posts I wrote on this blog were about the Hartle-Hawking and Vilenkin tunneling from "nothing" models, both of which are proposals for a quantum state of the universe (quantum cosmologies). Having read over these again and in light of Hawking's death I thought it might be useful to explain and contrast these in a single post, a bit more.

If I throw a sharpie acro…

Hey AronRa, Please Stop Talking Nonsense About Physics!

A couple of days ago I came across a video by AronRa on YouTube, a science popularizer who therein discusses the origin of the universe. I encourage everyone to watch the video before reading the rest of this post. A lot of the claims being made in the video are out right false but when they're sold to us by someone who may have a working knowledge of biology, or who drops technical language (a lot of which he himself doesn't understand), it makes it tempting for some people to be mislead by what he's saying.

I'm going to go through a few of the claims he's made ignoring all of the over the top, anti religious crap.

It's difficult to know if this first one (around 2:05) is a slip up or genuine ignorance. It's not the kind of mistake anyone with an actual understanding of the topic would make. He equivocates here between "expansion" and "inflation" as if they were the same thing. Inflation was first proposed by Starobinksy and Guth in th…

Chaotic Inflation Violates Penrose-Hawking Singularity Theorems

Claim: ChaoticInflation can avoid the implications of the Penrose-Hawking singularity theorem 

In the last post I talked about the Penrose-Hawking singularity theorem, and the conditions under which the theorem can be violated. One of the assumptions that Penrose and Hawking made was the strong energy condition, which states

This is true when the cosmological constant of the universe is zero, this has been a major weakness in their argument because neither the theorem nor the Friedman equation can tell us what the material or field content of the early universe was which has a direct affect on the pressure, mass density and expansion rate of the early universe. Under the second Friedman equation

If the pressure of matter p is positive then the rate of expansion is either decreasing or the rate of contraction is increasing but if the pressure is negative and the early universe is pervade by tension (a negative gravitational force) rather than normal pressure, then the expansion rate w…

Penrose-Hawking Singularity Theorems

Between 1965 and 1970, Penrose and Hawking proved a set of three singularity theorems together, all of which make varied assumptions and have different starting points. ** when a cosmologist refers to these as the "Penrose-Hawking Singularity theorem" they're mostly interested in the last theorem, which was proven in 1969 in a famous paper titled "The singularities of gravitational collapse and cosmology". This is the most powerful formulation of the Penrose-Hawking theorem, and it's what I'll talk about here.

Defining what a singularity is can be difficult. In some places you may find that a singularity appears in a model when the null or timelike geodesics cannot be extended indefinitely; that is to say, if the paths of photons or particles with mass terminate at some finite time into the past. Penrose-Hawking try to show that this condition obtain in our universe given some general features of spacetime.

Physically, interpreting that would mean that…

No Deal is Better than a Bad Deal

With the consent of both houses of parliament, Theresa May moved to trigger Article 50 back in March, making it the expressed will of not just one Prime Minister, but of the people and of their elected representatives. If the reality hasn't set in by now, it should have: we are leaving the European Union.

The only question that remains is whether we leave on favorable terms with an agreement in place that covers, not least of all trade or in keeping with the Prime Minister's oft-repeated phrase "no deal is better than a bad deal", we leave without a trade deal, and make the necessary arrangements to keep our economy competitive.

This latter option which involves tariffs, is how most countries conduct their trade with the European Union, we would in affect, be left with a "US-style" or "Chinese-style" relationship to the EU. One conducted on WTO terms, instead of a more favorable bilateral basis.

The possibility of leaving without a deal is hardly…