for the first and last time in the entire show, hamilton is rendered speechless. he can't come up with any words to sufficiently explain how he feels about laurens dying. he locks it down and only responds to eliza's concern with a tense "i have so much work to do". I do not think this is accidental, and the result is even more impactful in showing how badly hamilton is hurt than if he'd spilled his guts about it on stage for a whole number like he usually would.
we jump straight into non-stop... where we see burr constantly question "why do you write like you're running out of time? / like tomorrow won't arrive? / every second you're alive? / like you need it to survive? / ARE you running out of time?", which really brings into focus where all this motivation to work non-stop really comes from for Hamilton. he's coping with laurens' death by burying himself into work, yes, he wants to help build the nation laurens died for, yes, but his death also gave him a SLAP in the face and made him realize how fleeting life is, so he works himself into the ground trying to get as much done with his life before he dies, because no one really knows how long they have left, and it's easy to forget that until it happens to someone close to you.
edit: IN FACT, when hamilton says yes to washington's offer of treasury secretary, and eliza confronts him, his go-to argument is "look around, look around, how lucky we are to be alive right now". after philip was born, his motivation for working hard was gentle and soft: we'll bleed and fight for you, we'll make it right for you. it's only after laurens's death that such motivation turned extreme and urgent: I am alive and he's not. I need to make the most of my time while I'm still here, because he isn't.
PLUS in the film you can actually see hamilton WIPE A TEAR in the background before "gentlemen of the jury...", so it really shows that even after his seemingly cheerful chatter with burr he's still feeling sad about laurens.
EDIT #2 BECAUSE HOLY FUCK !!!!!!: alexander has grown seeing people he loved die since his childhood, and he's had to work his ass off to escape those circumstances. but then, in my shot, he says "for the first time I'm thinking past tomorrow", because he can actually see a future for himself for once. THEN... in nonstop... burr says "why do you write like tomorrow won't arrive?", because laurens's death has sent alexander spiraling back into a mindset of restless working as it's reminded him nobody's promised tomorrow
EDIT 3: when alexander goes to ask burr for help with the federalist papers, he tells him "what are you waiting for, what do you stall for?", and that specific phrase was first said by......... LAURENS, in aaron burr, sir. Alexander is literally using laurens's words to confront burr. so when he says "we studied, and we fought, and we killed, for the notion of a nation we now get to build", it really feels like he could've added "we died" on the list. he's all too aware of the sacrifice laurens gave for the revolution and he feels burr is just pissing on it by refusing to help create the new nation laurens died for
