What If The Speed of Light is NOT CONSTANT?
PBS Space Time・16 minutes read
The speed of light is constant and crucial in understanding the fundamental connection between space and time, affecting the rate of change in the universe and matter's internal dynamics. Variable speed of light theories challenge this constancy, breaking fundamental symmetries and requiring a new theory to surpass relativity in predictions, prompting a revisiting of episodes on superfluids, moving the Sun as a spaceship, detecting planet-sized spaceships with LIGO, and predicting nearby supernovas.
Insights
- The speed of light in a vacuum is a universal constant that underpins our understanding of the universe, influencing concepts like time, information transmission, and the connection between space and time.
- Variable speed of light theories challenge established principles like Lorentz invariance and CPT symmetry, necessitating a thorough reevaluation of foundational axioms in physics to ensure new theories are predictive and coherent, especially when reconciling relativity with quantum mechanics.
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Recent questions
How does the speed of light impact the rate of change in the universe?
The speed of light plays a crucial role in determining the rate of internal change for all matter in the universe. It serves as a unit conversion factor between spatial and temporal units, dictating the pace at which information can travel and influencing the fundamental connection between space and time. Any alteration in the speed of light would require a fundamental shift in the relationship between space and time, affecting the way in which the universe evolves and changes over time.
What is Lorentz invariance and its significance in physics?
Lorentz invariance precisely describes the invariance of the speed of light, stating that the laws of physics remain the same for all observers moving at constant velocities. This principle is fundamental in special and general relativity, forming the basis for our understanding of spacetime and the behavior of matter and energy. Any theory that breaks Lorentz invariance challenges the core principles of modern physics, potentially leading to new insights or revisions in our understanding of the universe.
How do variable speed of light theories impact existing physics theories?
Variable speed of light theories have been proposed to explain phenomena such as dark energy and gravity, deviating from the constant speed of light in a vacuum. These theories challenge the foundational axioms of existing physics theories, breaking Lorentz invariance and the fundamental CPT symmetry of the universe. It is essential to critically evaluate these theories, ensuring that any new theory surpasses the predictive power of current models, especially when challenging established frameworks like relativity and quantum mechanics.
Can the speed of light be changed, and what would be the consequences?
Changing the speed of light would require altering the fundamental connection between space and time, impacting the rate of internal change for all matter in the universe. The speed of light serves as a maximum speed limit for information travel, influencing the way in which energy and matter interact across spacetime. Any modification to the speed of light would have far-reaching consequences, potentially leading to significant shifts in our understanding of the fundamental laws of physics and the nature of the universe.
What are the implications of missed comment responses in recent episodes?
Due to recent missed comment responses, a selection of episodes will be revisited, including discussions on superfluids, turning the Sun into a spaceship, detecting planet-sized spaceships with LIGO, and predicting the next nearby supernova. These revisits aim to address any overlooked questions or comments, providing further insights into the topics covered in previous episodes. By revisiting these discussions, the show can ensure that all viewer inquiries are addressed and that the audience gains a comprehensive understanding of the scientific concepts presented.
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Summary
00:00
"Constant speed of light in universe"
- The speed of light in a vacuum is constant for all observers.
- Variable speed of light theories have been used to explain dark energy and gravity.
- Lorentz invariance precisely describes the invariance of the speed of light.
- Special and general relativity are based on the invariance of the speed of light.
- The speed of light is the maximum speed at which information can travel.
- Changing the speed of light would require altering the fundamental connection between space and time.
- Time is a measure of the rate of change in the universe.
- The speed of light dictates the rate of internal change for all matter.
- The speed of light is a unit conversion factor between spatial and temporal units.
- Variable speed of light theories break Lorentz invariance and the fundamental CPT symmetry of the universe.
14:03
Challenging Theories, Revisiting Episodes, Detecting Spaceships
- It is essential to question the foundational axioms of theories, ensuring any new theory surpasses the old one in predictions, especially when challenging relativity due to its clash with quantum mechanics.
- Due to recent missed comment responses, a selection of episodes will be revisited, including superfluids, turning the Sun into a spaceship, detecting planet-sized spaceships with LIGO, and predicting the next nearby supernova.
- In the discussion on superfluids, stirring a superfluid into a vortex is possible as the spoon imparts energy to the fluid, creating a new flow that can lead to rotation.
- Moving the Sun to different galactic orbits would not drag planets along with zero effect, as even a tiny change in the Sun's position alters the center of mass, requiring orbital shifts to maintain stability.
- Detecting gigantic spacecraft emitting gravitational radiation when accelerating is not limited to RAMAcraft, as head-on collisions between compact bodies like black holes or neutron stars can also produce detectable gravitational waves with unique signatures.
