Sunday, August 28, 2016

When will SUSY be wrong?

High energy particle physics theorists are disappointed and even dismayed that the Large Hadron Collider has shown up nothing beyond the Standard Model Higgs.  Their favorite "Beyond Standard Model" physics, based on an idea called supersymmetry (SUSY) has not shown even a tiny hint of existing.  Over on "Not Even Wrong", Peter Woit asked "“Is there any forseeable experimental data that would cause you to decide that SUSY was an idea that should be abandoned?”

Urs Schreiber gave a logical answer as to why physicists might think SUSY is relevant to physics - not just in a technical sense where it can make some computations tractable - but as a part of reality.  You can follow the link (or see below the fold).

So, I thought that Woit's question was answered.  Nothing but a mathematical theorem with a proof will serve to end the SUSY quest.  Namely, something like:
"Nature chose to have an ordinary group act on the supermanifold" because:

1. Using a supergroup on the supermanifold implies a necessary feature in the low energy theory that our observed low energy world lacks;  or

2. Our low energy world has an observed feature that the use of a supergroup on the supermanifold cannot reproduce; or else,

3. Using a supergroup on a supermanifold produces a high-energy theory that fails for some reason (without even considering the low energy world).
Since the question is: “Is there any foreseeable experimental data that would cause you to decide that SUSY was an idea that should be abandoned?”", (3.) above need not concern us here.  The Higgs as detected by the LHC, with nothing super- accompanying it, does not quite fall into either 1. or 2. without additional assumptions.

Therefore the SUSY search will continue.
Woit didn't like that answer and deleted it.

On a side note, Charles Darwin, around the time of spelling out his theory of evolution, also wrote: "It is mere rubbish thinking at present of the origin of life-- one might as well think of the origin of matter."  This is because he knew that the problem of the origin of life was well beyond the reach of the science of his time.  Particle physics theorists, however, have believed for about forty years that a complete description of fundamental physics is within their grasp.  Nature has proven to be rather elusive.

Tuesday, August 09, 2016

Hint of Rakhigarhi DNA news to come

The Times of India reports:
Scientists are anxiously awaiting complete re sults of the DNA tests of samples taken from Rakhigarhi. "We took DNA samples from skeletons recovered from the archeological dig as well as residents of Rakhigarhi village of today. The initial results have thrown up scientific evidence proving that even as the civilization faded away , some people adapted to the changes and continued to live here," the official added, requesting anonymity as the full results of the research project are not out yet.

Tuesday, July 26, 2016

Tying shoe laces

In each case, the link leads to a video that shows something that I did not know about tying shoe laces.

1. How to tie your shoes.

2. Running shoes.

Thursday, July 14, 2016

Rakhigarhi DNA news

Via the Indian Express:

“We have found what has not been found at any other Harappan excavation site before — a DNA extraction from the skeletal remains,” says Shinde, describing it as one of the biggest breakthroughs in Harappan research, “The important aspect that we are working, on which has never been done before, is the facial reconstruction of the Harappan people. The South Koreans have developed a software in which if we feed the DNA data along with the morphological features, like measurements of bones, it can help us reconstruct the face. For the first time, we will be able to see what Harappans looked like, the colour of their skin, their eyes and so on.”

The lab in Seoul has sent the reports of the tests, but Shinde says they can’t be made public yet. He, along with his team, have tied up with top universities for cross-verification of the data. “Their experts will come down to Hyderabad in July and confirm the data and reports that we have received. Once that is done, we will apply for the data to be published in a world-reputed journal and only after that will we reveal it to the media and rest of the world,” he says.

Sunday, July 10, 2016

Science?

The nerdy/geeky types have two obsessions - intelligence, and their self-perceived lack of social skills.  It is therefore a common theme with them that they have self-diagnosed Autism Spectrum Disorders; that autism is also somehow correlated with high intelligence; and that many great minds of the past had some or other Autism Spectrum Disorder. This somehow is very comforting to them.

Then there are the conservative anti-government types, who want to find a genetic basis (and so supposedly immutable) for difference in intelligence - and intelligence to them is a one-dimensional IQ score; they pay lip service only to the idea that intelligence is multi-dimensional, such as Howard Gardner's musical–rhythmic, visual–spatial, verbal–linguistic, logical–mathematical, bodily–kinesthetic, interpersonal, intrapersonal, and naturalistic dimensions. All achievement in life is highly correlated to this IQ according to these theorists. The idea is that immutable genetic differences make all government programs to help the less intelligent poor quite pointless.

Some of these themes come together in this recent paper:
Autism As a Disorder of High Intelligence

The abstract begins (emphasis added):
A suite of recent studies has reported positive genetic correlations between autism risk and measures of mental ability. These findings indicate that alleles for autism overlap broadly with alleles for high intelligence, which appears paradoxical given that autism is characterized, overall, by below-average IQ. This paradox can be resolved under the hypothesis that autism etiology commonly involves enhanced, but imbalanced, components of intelligence. This hypothesis is supported by convergent evidence showing that autism and high IQ share a diverse set of convergent correlates, including large brain size, fast brain growth, increased sensory and visual-spatial abilities, enhanced synaptic functions, increased attentional focus, high socioeconomic status, more deliberative decision-making, profession and occupational interests in engineering and physical sciences, and high levels of positive assortative mating.

For the highlighted part, e.g.,
Compared to What? Early Brain Overgrowth in Autism and the Perils of Population Norms

Elsewhere in the paper we see this:
However, a suite of recent studies, described in more detail below, has demonstrated that alleles “for” autism, that is, common alleles that each contributes slightly to its risk, overlap substantially and significantly with alleles “for” high intelligence (Bulik-Sullivan et al., 2015; Clarke et al., 2015; Hill et al., 2015; Hagenaars et al., 2016). To a notable, and well-replicated, degree, then, many “autism” alleles are “high intelligence” alleles. How can these paradoxical observations be reconciled?

When I chase the citations, I go, oh really? If I find the enthusiasm, then you might see more about it here.

Thursday, July 07, 2016

"Archaeological and genetic insights into the origins of domesticated rice"

Warning: the publications in my last series of posts was obtained by "cites" or "cited by", so there is a selection bias.  Not being an expert, I cannot provide the nuance and balance that might be necessary to interpret these publications.

http://www.pnas.org/content/111/17/6190.full.pdf
Archaeological and genetic insights into the origins of domesticated rice
Briana L. Gross and Zhijun Zhao

(emphasis added)
Excerpt:
India. The prehistory of indica and japonica in India presents one of the more interesting stories of domestication, long distance spread, and subsequent interactions of cultivars within a single genus of plants. Both O. rufipogon and another close wild relative, Oryza nivara, are native to India and well distributed there today, and probably were present since the Pleistocene (46). The country has a number of long archaeological sequences with good plant records including those in the Ganges River valley in the north where rice, likely wild O. rufipogon and O. nivara, is documented by 9000 BP (46,47). It is now recognized that the Indian subcontinent was probably an independent center of agricultural origins with important regions in the Ganges plain and to the south on the Deccan Plateau. Native plants that were cultivated or domesticated before crops were introduced from elsewhere include mung bean and small-seeded grasses, among others (47). The question of an origin of indica rice in India has been under active discussion, and recent research has done much to clarify and resolve the issue. It now appears that an independent origin of cultivation of ancestral indica or proto-indica rice took place in the Ganges plains, but that the plant was completely domesticated only when domesticated japonica arrived from China and hybridized with it about 4,000y ago (47). Indica consumption began early, by 8400 BP, and the plant was cultivated and appears to have been a staple food by 5000 BP (47).

"The Agricultural Revolution in Prehistory: Why did Foragers become Farmers?"

The (Barker 2006) reference found in the excerpt that I previously posted,  of "Cultural and Demic Diffusion of First Farmers, Herders, and their Innovations Across Eurasia" 

Our own simulations for the Indian subcontinent showed that the connection from the Indus region to the Levante was only established after the transition to agropastoralism (Lemmen and Khan 2012), consistent with the wheat/rice barrier identified by (Barker 2006).
is:
The Agricultural Revolution in Prehistory: Why did Foragers become Farmers? 1st Edition, by Graeme Barker

Large sections of the book are readable on amazon.com. I'm breaking my discipline by posting something without reading the whole book, but these, from the conclusion of chapter 5, Central and South Asia: the Wheat/Rice Frontier, I thought, would be a good motivation to get and read the book.


and:



"Cultural and Demic Diffusion of First Farmers, Herders, and their Innovations Across Eurasia"

http://arxiv.org/pdf/1502.00201v2.pdf  (PDF)
Cultural and Demic Diffusion of First Farmers, Herders, and their Innovations Across Eurasia
Carsten Lemmen

From the paper:

Our own simulations for the Indian subcontinent showed that the connection from the Indus region to the Levante was only established after the transition to agropastoralism (Lemmen and Khan 2012), consistent with the wheat/rice barrier identified by(Barker 2006).

From the paper:

"A simulation of the Neolithic transition in the Indus valley"

I didn't know arxiv.org carried papers on this subject:
https://arxiv.org/abs/1110.1091

Emphasis added.
A simulation of the Neolithic transition in the Indus valley
Carsten Lemmen, Aurangzeb Khan

(Submitted on 5 Oct 2011 (v1), last revised 7 May 2012 (this version, v3))
The Indus Valley Civilization (IVC) was one of the first great civilizations in prehistory. This bronze age civilization flourished from the end of the fourth millennium BC. It disintegrated during the second millennium BC; despite much research effort, this decline is not well understood. Less research has been devoted to the emergence of the IVC, which shows continuous cultural precursors since at least the seventh millennium BC. To understand the decline, we believe it is necessary to investigate the rise of the IVC, i.e., the establishment of agriculture and livestock, dense populations and technological developments 7000--3000 BC. Although much archaeological information is available, our capability to investigate the system is hindered by poorly resolved chronology, and by a lack of field work in the intermediate areas between the Indus valley and Mesopotamia. We thus employ a complementary numerical simulation to develop a consistent picture of technology, agropastoralism and population developments in the IVC domain. Results from this Global Land Use and technological Evolution Simulator show that there is (1) fair agreement between the simulated timing of the agricultural transition and radiocarbon dates from early agricultural sites, but the transition is simulated first in India then Pakistan; (2) an independent agropastoralism developing on the Indian subcontinent; and (3) a positive relationship between archeological artifact richness and simulated population density which remains to be quantified.
The authors point to a possible center of rice domestication ("Lahuredawa in the middle Ganges plains") as a possible source of agropastoralism.
Less favored by the model are the valleys along the Indo-Iranian plateau, where broad subsistence possibilities are seen as one precondition for the rise of the IVC and where agropastoralism arose before 6500 BC [Jarrige, 1995]. The model might underestimate the potential for agropastoralism in this area because of its coarse spatial scale.

FYI: Definition of agropastoral. : of or relating to a practice of agriculture that includes both the growing of crops and the raising of livestock.

Wednesday, July 06, 2016

The mythical link between poverty and terrorism

Back in 2014:
New research from Queen Mary University of London has found youth, wealth, and being in full-time education to be risk factors associated with violent radicalisation. Contrary to popular views – religious practice, health and social inequalities, discrimination, and political engagement showed no links.
The recent terror attack in Dhaka was committed by young, educated, highly privileged Bangladeshi youth.

Meanwhile, The Straits Times reports:
Two terror groups spread tentacles in Bangladesh
Officials say new breed of militants is efficient, highly educated, more organised.