दिवि सूर्यसहस्रस्य भवेद्युगपदुत्थिता । यदि भाः सदृशी सा स्याद्भासस्तस्य महात्मनः ॥12॥
If a thousand suns were to blaze forth together in the sky, they would not match the splendor of that great form.

Sanjay now describes the effulgence of the universal form. To give an idea of its dazzling radiance, he compares it to thousands of suns blazing simultaneously in the midday sky. Actually, God’s effulgence is unlimited; it cannot be quantified in terms of the effulgence of the sun. However, narrators often describe the unknown by extrapolating from the known. The simile of a thousand suns expressed Sanjay’s perception that the splendor of the cosmic form had no parallels.

https://www.holy-bhagavad-gita.org/chapter/11/verse/12

श्रीभगवानुवाच। कालोऽस्मि लोकक्षयकृत्प्रवृद्धो लोकान्समाहर्तुमिह प्रवृत्तः । ऋतेऽपि त्वां न भविष्यन्ति सर्वे येऽवस्थिताः प्रत्यनीकेषु योधाः ॥32॥
The Supreme Lord said: I am mighty Time, the source of destruction that comes forth to annihilate the worlds. Even without your participation, the warriors arrayed in the opposing army shall cease to exist.

In response to Arjun’s question regarding who he is, Shree Krishna reveals his nature as all-powerful Time, the destroyer of the universe. The word kāla is derived from kalayati, which is synonymous with gaṇayati, meaning “to take count of.” All events in nature get buried in time. When Oppenheimer, who was a part of the first atom bomb project, witnessed the destruction of Hiroshima and Nagasaki, he quoted this verse of Shree Krishna in the following manner: “Time…I am the destroyer of all the worlds.” Time counts and controls the lifespan of all beings. It will determine when the great personalities like Bheeshma, Dronacharya, and Karn will meet their end. It will destroy the enemy army arrayed on the battlefield even without Arjun’s participating in the fight, because the Lord wants it to happen as a part of his grand scheme for the world. If the warriors are already as good as dead, then why should Arjun fight? Shree Krishna explains this in the next verse.

https://www.holy-bhagavad-gita.org/chapter/11/verse/32

The joint work of the scientists at Los Alamos resulted in the world's first nuclear explosion, near Alamogordo, New Mexico, on July 16, 1945. Oppenheimer had given the site the codename "Trinity" in mid-1944 and said later that it was from one of John Donne's Holy Sonnets. According to the historian Gregg Herken, this naming could have been an allusion to Jean Tatlock, who had committed suicide a few months previously and had in the 1930s introduced Oppenheimer to Donne's work.[114] Oppenheimer later recalled that, while witnessing the explosion, he thought of a verse from the Bhagavad Gita (XI,12): divi sūrya-sahasrasya bhaved yugapad utthitā yadi bhāḥ sadṛṥī sā syād bhāsas tasya mahātmanaḥ[115]

If the radiance of a thousand suns were to burst at once into the sky, that would be like the splendor of the mighty one ...[5][116]

Years later he would explain that another verse had also entered his head at that time: namely, the famous verse: "kālo'smi lokakṣayakṛtpravṛddho lokānsamāhartumiha pravṛttaḥ" (XI,32),[117] which he translated as "I am become Death, the destroyer of worlds."[note 2]

https://en.wikipedia.org/wiki/J._Robert_Oppenheimer

śhrī-bhagavān uvācha
kālo ’smi loka-kṣhaya-kṛit pravṛiddho
lokān samāhartum iha pravṛittaḥ
ṛite ’pi tvāṁ na bhaviṣhyanti sarve
ye ’vasthitāḥ pratyanīkeṣhu yodhāḥ