Question 68 from UPSC CSE 2018 - General science and Science & Technology

Question

Consider the following statements:
1. Light is affected by gravity.
2. The Universe is constantly expanding.
3. Matter warps its surrounding space-time.
Which of the above is/are the prediction/predictions of Albert Einstein's General Theory of Relativity, often discussed in media?

IASCODEX · Accepted Answer

Correct Option: D. 1, 2, and 3

Strategy: Focus on what Einstein's General Theory of Relativity introduced — gravity as curvature of space-time, effect on light, and dynamic universe concepts. Statement 1 (light is affected by gravity) and statement 3 (matter warps space-time) are direct predictions. Statement 2, the expanding universe, also arises from Einstein's equations, later confirmed by observation. Therefore, all statements are correct.

Key Info: Albert Einstein's General Theory of Relativity, formulated in 1915, fundamentally altered the understanding of gravity. According to the theory:

- Matter warps or curves the surrounding space-time fabric. This curvature directs the path of matter and light, replacing Newtonian gravity's force model (Statement 3).
- Light is affected by gravity; this is demonstrated by gravitational lensing, where light passing near a massive object bends, confirmed experimentally during the 1919 solar eclipse (Statement 1).
- Einstein's equations permitted a dynamic universe, allowing for solutions where the universe could expand or contract. Although Einstein initially introduced a 'cosmological constant' to favor a static universe, later observations by Edwin Hubble (1929) of cosmological redshift established that the universe is indeed expanding, consistent with General Relativity (Statement 2).
- The theory also predicts phenomena such as black holes and gravitational waves, all of which have subsequently been observed.

General Relativity replaces the concept of gravity as a force with the idea of mass-energy shaping the geometry of space-time, influencing the motion of objects and light, and providing the framework for modern cosmology.

IASCODEX · Answer

Option A: 1 and 2 only

IASCODEX · Answer

Option B: 3 only

IASCODEX · Answer

Option C: 1 and 3 only

Consider the following statements: Light is affected by gravity. The Universe is constantly expanding. Matter warps its surrounding space-time. Which of the above is/are the prediction/predictions of Albert Einstein's General Theory of Relativity, often discussed in media?

Consider the following statements:

Light is affected by gravity.

The Universe is constantly expanding.

Matter warps its surrounding space-time.
Which of the above is/are the prediction/predictions of Albert Einstein's General Theory of Relativity, often discussed in media?