The Beginning Of The Universe For Beginners
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The Universe: A Fascinating Study
The universe is a captivating entity, housing everything from the immensely large to the incredibly small. Despite some less appealing aspects, scholars generally agree that its existence is a positive phenomenon. This belief has led to the development of an entire scientific field dedicated to studying the universe, known as cosmology.
The Role of Cosmologists
Cosmologists focus on what exists in space and strive to piece together the story of how our universe evolved. They seek to understand what the universe is currently doing, what it will do in the future, and how it all began. It was Edwin Hubble who first observed that our universe is expanding, as he noted that galaxies seem to be moving further apart. This observation implied that everything must have started with an immense explosion from an infinitely hot, infinitely small point. This concept was initially referred to as the “Big Bang” in a joking manner, but as evidence accumulated, both the idea and the name stuck.
Post-Big Bang Universe
Post-Big Bang, the universe cooled down to form the stars and galaxies that we observe today. Cosmologists have numerous theories about how this process occurred. However, we can also explore the origins of the universe by recreating the hot, dense conditions that existed at the beginning of time in a laboratory setting. This task is undertaken by particle physicists.
The Role of Particle Physicists
Over the past century, particle physicists have been studying matter and forces at increasingly higher energies. Initially, they used cosmic rays, and then moved on to particle accelerators, machines that collide subatomic particles at high energies. The higher the energy of the accelerator, the further back in time they can effectively look.
Understanding the Early Universe
Today, the universe is largely composed of atoms, but hundreds of seconds after the Big Bang, it was too hot for electrons to join atomic nuclei to form atoms. Instead, the universe was made up of a swirling sea of subatomic matter. A few seconds after the Big Bang, it was even hotter, hot enough to overpower the forces that usually hold protons and neutrons together in atomic nuclei. Further back, microseconds after the Big Bang, protons and neutrons were just beginning to form from quarks, one of the fundamental building blocks of the standard model of particle physics. Even further back, the energy was too great for even the quarks to stick together.
The Future of Particle Physics
Physicists hope that by reaching even greater energies, they can see back to a time when all the forces were one and the same. This would simplify the understanding of the origins of the universe. To achieve this, they’ll need to build bigger colliders and work hard to combine our knowledge of the very big with the very small. They will also need to share these fascinating insights with each other and with the public. After all, when it comes to our universe, we’re all in this together.
Discussion Questions
- What is cosmology and why is it important in studying the universe?
- How did Edwin Hubble’s observation of the expanding universe contribute to our understanding of its origins?
- What are some theories about how stars and galaxies formed after the Big Bang?
- What role do particle physicists play in understanding the early universe?
- How have particle physicists been able to study matter and forces at increasingly higher energies?
- What was the universe like in the moments after the Big Bang, before atoms formed?
- What are physicists hoping to discover by reaching even greater energies in particle accelerators?
- Why is it important for physicists to share their findings with each other and the public?
Lesson Vocabulary
universe – all existing matter, space, and time as a whole – The universe is believed to be expanding at an accelerated rate.
cosmology – the study of the origin, structure, and evolution of the universe – Cosmology attempts to explain the large-scale properties of the universe.
cosmologists – scientists who study the origin, structure, and evolution of the universe – Many cosmologists are working to understand the nature of dark matter.
Big Bang – the prevailing theory for the origin of the universe, suggesting it started as a singularity and expanded rapidly – According to the Big Bang theory, the universe began approximately 13.8 billion years ago.
particle physicists – scientists who study the fundamental particles and forces that make up the universe – Particle physicists use particle accelerators to study the behavior of subatomic particles.
matter – a physical substance that occupies space and has mass – All living organisms are composed of matter.
forces – interactions that cause a change in motion or shape of an object – Gravity and electromagnetic forces are fundamental forces in nature.
atoms – the basic units of matter, consisting of a nucleus surrounded by electrons – All elements are composed of atoms.
quarks – subatomic particles that combine to form protons and neutrons – Quarks are never found alone but are always bound together in particles.
colliders – large machines that accelerate particles to high speeds and collide them together – The Large Hadron Collider is the world’s largest and most powerful particle collider.
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- Categories: Earth & Space Science, TED Ed, Video Lessons
- Keywords: atoms, Big Bang, colliders, cosmologists, cosmology, forces, matter, particle physicists, quarks, universe
