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1Urquhart
Jun 4, 2016, 4:49pm


Synthetic humans not far away?

http://news.google.com/news/section?cf=all&pz=1&ned=us&topic=snc&amp...

Your favorite scientific theory? Mine is gravity. I still can't figure out that everything falls at an equal rate.

Your least favorite theory? Mine is jet propulsion. I would much rather fly in a plane where I see the propellers going around. Anything other than that is just faith.

2vy0123
Jun 6, 2016, 5:49am

https://youtu.be/wsixsRI-Sz4

The neurolace Elon speaks of can it interface io at the gap between the left and right hemispheres of the brain? Outwardly will it have an antenna hanging down like the rat's tail hairstyle or Qing dynasty Chinese queue?

3proximity1
Jun 6, 2016, 8:58am



"SGE" -- "Stochastic gene expression" --also known as "Ontophylogenesis"

@ scienceforums (dot) net

"On Ontophylogenesis or "Cellular Darwinism"
Started by proximity1, Sep 03, 2012


Key researchers: Dr. Jean-Jacques KUPIEC , Centre Cavaillès, Paris, France ,

Library Thing author page : Jean-Jacques Kupiec

Dr. Pierre SONIGO,

See these works:

L'origine des individus
Ni Dieu ni gène

4proximity1
Editado: Jun 7, 2016, 4:26am

Tweny-three Chromosome Pairs? Try 1,000! @ "Science Over a cuppa" the home blog of Emily Casanova, developmental, molecular and cell biologist.



June 5, 2016 · by Emily Casanova ( Bookmark the permalink )

"Every once in awhile, maybe once in a blue moon, you may read something that’s so left-field, so alien that it literally changes your fundamental concepts. For me that happened last weekend as I read a paper by Hannibal et al. (2014) that has triggered in me a conversion event in how I view Genetics, “the Big G.”

"Many of you have probably heard by now that even though the cells of our body have the same basic DNA template, there can be minor (or in the case of tumor cells perhaps even major) differences between them. But in spite of these differences, for the most part we tend to treat each cell from the same organism as if it essentially has the same genome as its neighbor. In the case of humans: that’s 23 chromosome pairs, with the same genes and the same nucleotide sequences, give or take the occasional mutation or rearrangement."

Paper cited :


Copy Number Variation Is a Fundamental Aspect of the Placental Genome at PLOS Genetics

Roberta L. Hannibal,
Edward B. Chuong,
Juan Carlos Rivera-Mulia,
David M. Gilbert,
Anton Valouev,
Julie C. Baker

PLOS

Published: May 1, 2014

http://dx.doi.org/10.1371/journal.pgen.1004290

5proximity1
Editado: Ago 18, 2016, 2:37pm

Has a Hungarian physics lab found a fifth force of nature? : Journal Nature ...


Nature (excerpt)

... "Krasznahorkay says his group was searching for evidence of just such a dark photon – but Feng’s team think they found something different. The Hungarian team fired protons at thin targets of lithium-7, which created unstable beryllium-8 nuclei that then decayed and spat out pairs of electrons and positrons. According to the standard model, physicists should see that the number of observed pairs drops as the angle separating the trajectory of the electron and positron increases. But the team reported that at about 140º, the number of such emissions jumps — creating a ‘bump’ when the number of pairs are plotted against the angle — before dropping off again at higher angles.

Bump in confidence

"Krasznahorkay says that the bump is strong evidence that a minute fraction of the unstable beryllium-8 nuclei shed their excess energy in the form of a new particle, which then decays into an electron–positron pair. He and his colleagues calculate the particle’s mass to be about 17 megaelectronvolts (MeV).

“We are very confident about our experimental results,” says Krasznahorkay. He says that the team has repeated its test several times in the past three years, and that it has eliminated every conceivable source of error. Assuming it has done so, then the odds of seeing such an extreme anomaly if there were nothing unusual going on are about 1 in 200 billion, the team says." ...



------------
Source article :

http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.116.241103

6jjwilson61
Ago 18, 2016, 2:34pm

>1 Urquhart: Your favorite scientific theory? Mine is gravity. I still can't figure out that everything falls at an equal rate.

Just try a mind experiment. You and a friend of equivalent weight are both free-falling next to each other separately, and then you hold hands. Do you think you'd fall twice as fast after holding hands?

7proximity1
Oct 22, 2016, 10:57am

Physicsworld.com

Super-Novae analysis finds scant evidence for "dark matter."


••• new statistical analysis of type 1a supernovae observations has failed to find substantial statistical evidence that the rate of expansion of the universe has been increasing over time. Instead, the calculations are consistent with a universe that is expanding at a mostly constant rate – something that could be at odds with the popular lambda-cold dark matter (ΛCDM) model of cosmology.

Type 1a supernovae are exploding stars that play an important role in astronomy as "standard candles" that emit the same type and quantity of light. This means that the distance to a supernova can be worked out simply from its brightness in the sky.

Prior to the late 1990s, cosmologists had assumed that the expansion of the universe should either be constant over time, or slowing down. But then a team led by Saul Perlmutter and another team led by Adam Riess and Brian Schmidt noticed that the rate of expansion of the universe has been increasing. The teams found that more than 50 distant type 1a supernovae are fainter than expected for their measured redshift.

The expansion of the universe causes the light from a supernova to be shifted to longer wavelengths when observed on Earth. This redshift tells astronomers how quickly the supernova was moving away from us when the explosion occurred – which gives us the rate of the expansion of the universe at that time.

Surprise discovery

The surprise discovery was evidence that the expansion of the universe has been accelerating. It earned Perlmutter, Riess and Schmidt the 2011 Nobel Prize for Physics and led physicists to speculate that this acceleration was driven by an unseen entity called dark energy.

Since then, further independent evidence for the accelerating expansion has come to light in measurements of the cosmic microwave background (CMB) and observations of galaxies. Indeed, the accelerating expansion of the universe has become a pillar of the most popular theory of cosmology, ΛCDM, where Λ is the cosmological constant that describes the acceleration.

Hundreds of other type 1a supernovae have been observed since the 1990s, but now some physicists are beginning to doubt whether these observations support an accelerating expansion. Subir Sarkar of the University of Oxford in the UK, Jeppe Nielsen of the Niels Bohr International Academy in Denmark and Alberto Guffanti of Italy's University of Turin have done a statistical analysis of data from 740 type 1a supernovae and concluded "that the data are still quite consistent with a constant rate of expansion".

Overly simple

The difference between the trio's study and previous analyses is how variations in supernovae light are dealt with.

While all type 1a supernovae are nearly identical, astrophysicists know that there are important differences that must be accounted for. Sarkar and colleagues argue that the statistical techniques adopted for previous studies are too simple and not appropriate for the growing set of observational data.

Using a technique that Sarkar describes as "industry standard statistics," the trio took a different approach to dealing with variations in the supernovae. They concluded that the deviation from a constantly expanding universe is less than about 3σ { 3 x "Sigma," the observed data's standard variation, }, which is a relatively poor statistical significance. "The evidence for accelerated expansion is marginal," says Sarkar, who believes that the ΛCDM model needs rethinking.

Roberto Trotta of Imperial College London does not go that far, pointing out that there is other independent and strong evidence for the accelerating expansion. However, he acknowledges that the evidence for acceleration in type 1a observations does not appear to be as robust as previously thought. Trotta – who has developed a new statistical method for analysing type 1a data that is different than Sarkar's – says that astronomers are poised to observe thousands of new type 1a supernovae and must be prepared to adopt more rigorous statistical techniques to analyse them.

The analysis is described in Scientific Reports.
About the author

Hamish Johnston is editor of physicsworld.com
http://physicsworld.com/cws/article/news/2016/oct/21/supernovae-analysis-finds-s...

8proximity1
Editado: Feb 20, 2017, 11:37am

News release : "Solving five big questions in particle physics in a SMASH:
Extension of the standard model provides complete and consistent description of the history of the universe"

from "DESY" : Deutsches Elektronen-Synchrotron, A Research Centre of the Helmholtz Association

http://www.desy.de/news/news_search/index_eng.html?openDirectAnchor=1176

Related to this news :

"Synopsis: Model Tries to Solve Five Physics Problems at Once" @
http://physics.aps.org/synopsis-for/10.1103/PhysRevLett.118.071802

"Scientists SMASH five of the biggest mysteries of modern physics" @
https://cosmosmagazine.com/physics/scientists-smash-five-of-the-biggest-mysterie...

------------------

Physical Review Letters : "Unifying Inflation with the Axion, Dark Matter, Baryogenesis, and the Seesaw Mechanism"

Authors : Guillermo Ballesteros, Javier Redondo, Andreas Ringwald, and Carlos Tamarit
Phys. Rev. Lett. 118, 071802 (2017) - Published 15 February 2017

Link: http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.118.071802

9proximity1
Abr 30, 2019, 11:44am


Recently published
____________________

(academic paper)

Self-Similar Processes Follow a Power Law in Discrete Logarithmic Space

by Mitchell G. Newberry and Van M. Savage

Phys. Rev. Lett. 122, 158303 – Published 19 April 2019

https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.122.158303

Tags: Biological Physics,General Physics,Networks
Statistical Physics,
Interdisciplinary Physics,
Fluid Dynamics