# Category Archives: Cosmology

## Shape of the universe: could it be curved, not flat?

Author: Eleonora Di Valentino is a postdoctoral researcher in astrophysics, University of Manchester Dark matter and gas in the universe. There may be more dark matter than we think.Illustris, CC BY-SA

No matter how elegant your theory […]

## The road to quantum gravity (4): The flow of time for massive objects

We started this series discussing the basic ingredients of the Universe: events, spacetime, causality. In the last chapter, we introduced massive objects (and thus, matter), which appear as a generalization of the so-called photon box.

As it moves, any […]

## The road to quantum gravity (3): The speed of light and the origin of mass

In the previous chapter of this series, we went over the subjective, relative separation of the network of events known as Spacetime into space and time. The speed of light played a major role in the discussion.

In particular, we […]

## The Road to Quantum Gravity (2): The emergence of Space and Time

The division of past and future

In Part 1 of this series, we presented the empirical fact that under extreme circumstances, a certain observer’s past can be in another observer’s future. To explain this, we introduced the network of […]

## The dark collapse of merging galaxies as the origin of supermassive black holes

I remember very well my physics professor during my first year at university. She stressed the importance of having clear intuitions of what physical terms mean before any mathematics was invoked. ‘Imagine someone drops an 100-gram apple 1 metre above […]

## The road to quantum gravity (1): Spacetime as the network of causality

Observations vs intuitions

Einstein’s Theory of Relativity introduced us to the concept of Spacetime, as a unified entity. This stands in contrast with the intuition that we develop since birth, which leads to naturally separate space and time.

Human intuition […]

## Ice Cube, the frozen observatory

Deep in the ice below the Amundsen-Scott South Pole Station, in Antartica, lies one of the great works that our modern civilization has produced. A kilometer and a half under the frozen surface there is a very special place for […]

## The search for cosmic inflation

The Big Bang Theory is one of the most robust theories ever made, if not the most. It also has become one of the greatest shows of our time, and I am not talking about the TV show with […]

## Hawking’s information preservation and weather forecasting mess

Last month, a lot of newspapers and websites have been promoting this article on Nature referring to a recent preprint uploaded by Stephen W. Hawking to the internet repository ArXiv. In this work, summarizing what he talked about in a […]

## Solid state physics could teach us how to quantize gravity: Horava’s theory

One of hottest topics in theoretical physics today is, of course, quantum gravity. The fact that, almost a hundred years after the born of the quantum theory, we still not have a functional theory that describes gravity at a microscopic […]