Many unanswered questions in cosmology

The Big Bang a unproved conjecture happened 13.8 Billions years ago, assuming that it really happened, Big Bang started from singularity which arises from using Einstein’s equations for gravity. Its very very long time ago, many things or process might have happened and they don't  exits now .The only resources we have to find what happened 13.8 Billions back are the telescope however sensitive it may be and the light (electromagnetic waves) . These tools may not be enough to predict what happened since Big Bang. To correctly predict all the events that have happened right from the Big Bang we need to have all or most of the recordings of all the events which is almost impossible.

Whether why matter dominated the antimatter or who turned on the Higgs field to give the mass to the particles are very difficult or almost impossible to predict. 

Many more questions remained unanswered ,what was there before Big Bang, what caused Big Bang and do we have single universe or multi-universe. The dark matter and dark energy still a mystery . Finally how universe is going to end in a big crunch or ripped apart because of endless expansion. 

We are still in search of a single theory often referred to "theory of everything" which can combine both Einstein general theory of relativity which applies to large structures of universe and the quantum theory which applies to subatomic particles. A single theory which unifies all the fundamental forces of universe. I mean quantum gravity .

The most important fact is that many process are difficult to replicate in laboratory. But scientific endeavor continues.

How Big Is The Sun Compared To Earth

The radius of Earth at the equator is 6,378 kilometers, however Earth is not quite a sphere.The planet's rotation causes it to bulge at the equator. Earth's polar radius is 6,356 km  a difference of 22 km.

The sun is nearly a perfect sphere. Its equatorial diameter and its polar diameter differ by only 10 km. The mean radius of the sun is 696,000 kilometers.

Volume of a sphere is V = 4/3 πr³

The ratio of volume of sun to Earth =  (4/3 πR³ ) / (4/3 πr³)

                                                             = (R/r)³

Where R is the radius of Sun and r radius of Earth

The ratio of Sun to Earth radius = R/r = 696,000/6,378  = 109.125

The ratio of volume of sun to Earth = (R/r)³ = (109.125)³ = 1299489 or approximately 1.3 million earths can fit inside Sun. 

The mass of the sun is  1.9891 x 10³⁰ kg about 333,000 times the mass of the Earth. The Sun contains 99.8 percent of the mass of the entire solar system.

   

Einstein Deserves Nobel Prize For Relativity

Einstein was disappointed that he did not receive Nobel prize for the theory of relativity instead he was awarded Nobel prize for photoelectric effect in 1921 ,actually he received it in 1922 . He proposed both photoelectric and relativity theory in 1905 .

Einstein general theory of relativity describes how gravity can distort the path of light,altering its trajectory called gravitational lensing. He was denied Nobel prize because committee decided against his work on the grounds that relativity was unproven. 

Cambridge astrophysicist Arthur Eddington measured the deflection of stars' positions near the Sun, the size of the deflection was exactly as Einstein had predicted from relativity in 1915 using total eclipse. But still he was denied because of the war and politics or may be antisemitism.

Albert Einstein also predicted the existence of gravitational waves in 1916 in his general theory of relativity. According to his theory  massive accelerating objects such as neutron stars or black holes orbiting each other would disrupt space-time in such a way that waves of distorted space would radiate from the source and the ripples would travel at the speed of light through the Universe.

After 100 years of Einstein General theory of Relativity prediction of gravitational waves gets a Nobel prize for the discovery of gravitational waves using the LIGO detector. Nobel Prize was awarded to Rainer Weiss of the Massachusetts Institute of Technology and Barry Barish and Kip Thorne of the California Institute of Technology, all members of the Ligo team. 

One of the most famous equations E=mc²  which revolutionized science comes from special theory of relativity, could have got a Nobel prize on its own. The significance of this equation is that mass and energy are different forms of same thing and transmutable.

Today's solar energy revolution is because of Einstein theory of photoelectric effect. Einstein should have won more than one Nobel Prize.

The Cosmological Constant

The cosmological constant was originally introduced by Einstein in 1917 as a repulsive force required to keep the Universe in static equilibrium which follows steady-state-theory. In trying to solve the differential equations that describe space-time, his field equations predicted that the universe should be either contracting or expanding. In the year 1922, Russian physicist Friedmann derived solutions to Einstein's equations that corresponded to an expanding universe. Einstein needed to add a constant term to avoid having the universe collapse upon itself. This term balances the attractive force of gravity contributed by all of the matter in the universe.  

Hubble's study of nearby galaxies showed that the universe was in fact expanding and that lead to the Big Bang theory, the concept introduced in 1927 by Georges LeMaitre.Einstein regretted the introduction cosmological constant to keep the universe static and termed it as greatest mistake.

After almost 100 years we realized that the Universe does in fact have a non-zero cosmological constant: that’s what we call dark energy, and use to explain the accelerated expansion of the Universe. Physically, this term represents the vacuum energy, the possibility that empty space possesses density and pressure thus preventing the universe from collapsing.

If indeed the cosmological constant represents the dark energy or vacuum energy then Einstein by mistake proposed the dark energy concept.

Why Diamond The Strongest Element

Graphite and Diamond are allotropes of carbon ,meaning any of two or more physical forms in which an element can exit. Diamond is very strong in fact strongest known where as graphite is very soft. Why ?

Let us look at the electronic configuration of carbon, it has 4 valence electrons and each carbon atom is covalently bonded to four other carbon atoms in case of diamond.The crystal structure of a diamond is a face-centered cubic or FCC lattice. Each carbon atom joins four other carbon atoms in regular tetrahedrons (triangular prisms).

Diamond's strength comes from pyramid-like structure which is the strongest structures known to man, This is a giant covalent structure and it continues on and on in three dimensions. It is not a molecule, because the number of atoms joined up in a real diamond is completely variable depending on the size of the crystal. As all the four electrons form covalent bonds, there are no free electrons or ions in diamond, so it does not conduct electricity. It has very high melting point (almost 4000°C) because very high temperatures are required to break the covalent bonds. Each carbon atom is at the same distance to each of its neighbouring carbon atoms. In this rigid network atoms cannot move. This explains why diamonds are so hard and have such a high melting point.

Graphite has a layer structure, each carbon atom uses three of its electrons to form simple bonds to its three close neighbours. The fourth electron is free and no longer associated directly with any particular atom or pair of atoms meaning delocalized, but are free to wander throughout the whole sheet.The distance between the layers is about 2.5 times the distance between the atoms within each layer. A weak Van der Waals force of attraction acts between the layers and these layers of  carbon slide over each other in graphite, that's why it is very soft and conducts electricity.

Climate Change And Rejuvenating The Rivers

Its very heartening to know that Sadhguruji has raised the issue of reviving and rejuvenating the rivers with 'Rally for Rivers' campaign,but people may want to know what is the plan of action .Basically rivers are nothing but carriers of rain water and hence we can't actually control them, depends more on the climatic conditions. Increasing the forest coverage and planting trees along the riversides as suggested by him may help somewhat. 

We are presently facing serious green house effect through burning of fossil fuels and made the earth more warmer  which could have disastrous consequences like  loss of snow cover, sea level rise, change in weather patterns. Many scientists believe that the damage to the Earth's atmosphere and climate is past the point of no return, meaning almost irreversible.

Atmospheric CO2 levels have increased by more than 40 percent since the beginning of the Industrial Revolution, from about 280 parts per million (ppm) in the year 1800 to 400 ppm today.There was a  landmark Paris agreement on climate change effective from  Nov. 4  2016 to strengthen the global response to the threat of climate change by keeping a global temperature rise this century well below 2 degrees Celsius above pre-industrial levels and to pursue efforts to limit the temperature increase even further to 1.5 degrees Celsius. Controlling and reducing the use of fossil fuels and the urgency to go for renewable energy is the need of the hour.

India has another big problem on hand, severe river pollution , Majority of Indian rivers are polluted because of industrial and human waste,particularly the Ganges . Our immediate concern must be to stop polluting the rivers and start cleaning them which requires massive effort from the government ,industries as well the people. Reducing consumption or usage of a polluting products,treatment of wastes, discharges and disposals of a pollutants. Govt. need to shutdown all the industries causing the river pollution or have strict guidelines for the industries to treat the pollutants and have proper waste management.

It is time for concerted action by world leaders on climate change . The climate change certainly made Harvey and Irma worse though they are not caused by climate change. Hurricanes thrive over warm water and strengthen in intensity, oceans have warmed on an average 1 to 3 degrees Fahrenheit. Climate change is a harbinger of doom.Time to act or face the consequences.