Question

The age of the universe is expected to be _______
1. 10⁴¹ second
2. 10²⁷ second
3. 10³⁷ second
4. 10¹⁷ second

Answer 1

Correct Answer - Option 4 : 10¹⁷ second

CONCEPT:

• It is believed that the age of the universe is around 13 billion years.

13 billion years = 1017 second.

EXPLANATION:

• None knows the exact age of the universe, but it is believed that it is around 13 billion years.
• The age of the universe is estimated in two ways:

1. by looking for the oldest stars;
2. by measuring the expansion rate of the universe and extrapolating it back to the Big Bang.

• Although the numbers are still very uncertain, the different data sets (also above two) are starting to converge at an age for the universe of about 12 to 13 billion.

13 years = 10¹⁷ second.

• So it is possible and estimated that the age of the universe is around 10¹⁷ seconds.
• Hence the correct answer is option 4.

• 10¹⁷ seconds is the longest interval of time that we have seen for anything till now.
• The shortest is 10^-24 for the life span of most unstable particles.