What If Gravity No Longer Existed?

Gravity is one of the primary life forces of the universe. Without it, not only would pretty much everything cease, but the very production of everything would fall apart. No more stars, no more planets, and nothing to keep us tethered to our home planet. Floating about may sound cool for a split second, but let me assure you, that would be a very, very bad thing (space is scary and we would die). Despite gravity being the very essence of our physical universe (it provides the attraction that ultimately allows things to come together and coalesce), our understanding of how it operates is poor at best. It"s believed to be the consequence of the warping of spacetime allotted by objects that have mass. At least, that"s what general relativity postulates, but the jury is still out on that one.

Anyhow, per our theories, gravity on Earth can"t just "turn off" (well, not without the planet and everything on it becoming obsolete). Nevertheless, we can still deal in hypotheticals. So if gravity did turn off (with the three remaining forces of the universe kept in check), what would happen?

Find out at:
http://www.fromquarkstoquasars.com/what-if-gravity-no-longer-existed/

Image:
http://zbush.deviantart.com/art/Chaos-of-2012-110574677

Loss of Gravity and Other Terrible Things: How Does the Human Body Act in Space?

You’ve probably been told many, many times that everything in the cosmos is connected. As John Muir so eloquently put it, “When we try to pick out anything by itself, we find it hitched to everything else in the Universe.” But what does this mean, exactly? Today, I want to explore this statement by looking at how we are connected to our planet.

We obviously need the Earth for food, water, air, and all the other basic necessities, but what I really want to do is explore how we rely on this planet in ways that, perhaps, we’ve never even considered. And to me, it seems that the best way to explore our connectedness to the planet is to leave it behind…and take a short trip into space.

Going to space can be awesome, but it can also be terrible. Find out why at:
http://www.fromquarkstoquasars.com/how-does-the-human-body-act-in-space/

Image source:
Daniel and Daniels

Tidal Stresses - How Gravity Heats Things Up

Our planet is able to sustain warmth because of its atmosphere and its proximity to the Sun. However, as you may know, most of the other planets aren"t so lucky; nearly all of them have rather frigid temperatures.

For example, take a look at moons like Enceladus or Europa. These moons (of Saturn and Jupiter, respectively) are known as "icy moons." As a result of the extreme temperatures, which are hundreds of degrees below zero, both moons have a thick layer of ice many kilometers deep; however, we know that liquid water still exists on them. How can this be?

Find out at:
http://www.fromquarkstoquasars.com/tidal-stresses-how-gravity-heats-things-up/

Image source before editing:
NASA

Unifying Gravity and Quantum Mechanics:

Quantum mechanics may seem like it is beyond our realm of experience; however, it is an integral part of the physics that governs our lives. Yet, it is not without its problems. There is one very important aspect of our everyday experience that is not described in a quantum framework-- and that is gravity. Because it keeps matter together, gravity is one of the driving forces of the cosmos -- and of life itself.

For quite some time, we have struggled with the goal of uniting gravity and quantum mechanics. Nowadays, physicists have had many ideas (some great, others not so much); however, nothing experimentally verifiable (like string theory) has surfaced. That is, until now.

Some physicists are starting to think that gravity itself is the ultimate decoherence, or the weakest form of background noise. To learn about new experiments that can help us solve this problem, see:
http://www.fromquarkstoquasars.com/unifying-gravity-and-quantum-mechanics/

Image source:
NASA

The Problem with Quantum Mechanics and General Relativity:

The quantum realm is rife with enigmas -- inexplicable things that leave us puzzled. Unsurprisingly, since we have the (modest) ambition of obtaining a complete mathematical picture of the entire universe, it seems like there are many properties of particle physics that are completely removed from our existence on Earth. However, that previous sentence is a bit of a paradox, because the quantum world is utterly ingrained into our surroundings. For starters, it can be seen emanating from the sun, as photons of electromagnetism bounce off of everyday objects, before arriving near our retinas. It can also be seen in the form of waves slamming into the shorelines, with the molecules of water slowly eroding large rocks into tiny pebbles of sand. These tiny grains, in turn, accumulate by the trillions, eventually forming the beaches we all love.

In short, we know that the realm of the very small is intricately related to our everyday experiences, and that our level of existence is only a tiny piece of a much larger puzzle. To progress as a species, it is imperative that we have a comprehensive understanding of the world around us.

However, we have had a hard time uniting the physics of the very small with the physics of the very large – Quantum Mechanics and General Relativity. To learn all about this problem, see:
http://www.fromquarkstoquasars.com/the-problem-with-quantum-mechanics-and-general-relativity/

Image source:
CERN

4 of the most Astounding Black Holes:

Black holes are some of the most amazing cosmological structures in the universe. We are drawn to them. Perhaps this is because they stand as a kind of sublime horror; they are super massive objects that consume entire worlds. Plus, their awesome size and power is unutterably amazing. However, despite their grandeur, they are exceedingly difficult to study. Try as we may, we really can’t get to the heart of these objects; the singularities themselves rest beyond the realm of physics. But all is not lost. Although we don’t know everything about black holes, we have uncovered some pretty amazing facts. Here, in no particular order, are some of the coolest black holes we’ve ever discovered.

To read about these amazing black holes, see:
http://www.fromquarkstoquasars.com/4-of-the-most-astounding-black-holes/

Image source:
NASA

Dropping a Hammer and Feather on the Moon (video post)

Have you ever seen a feather and a hammer dropped from the same height at the same time and land together? It is rather hard to accomplish this feat on Earth, as the air usually causes the two to land at different times. But the same isn"t true on the Moon. In the image pictured here, artist Alan Bean depicts Davin Scott preforming the hammer and feather experiment on the Moon during the Apollo 15 mission. And seeing this happen in a 40-second video clip is probably one of the coolest things I’ve seen in a long time.

Even though the feather and the hammer have different weights, in this video, you will see them hit the ground at the same time. Why does this happen? It is all because of a property of gravity discovered by Galileo Galilei. As you may have heard, he discovered the principle of gravitational acceleration (or acceleration due to gravity) by taking various objects to the top of the Tower of Pisa and dropping them. Later, Galileo devised a method to measure this acceleration by rolling balls down an incline.

To see the video of gravity in action, go to:
http://www.fromquarkstoquasars.com/dropping-a-hammer-and-feather-on-the-moon-video-post/

Image source: Alan Bean
http://www.alanbeangallery.com/hammerfeather-story.html