Rufus had never actually been on the paddle boats at Golden Gate Park, so Jiya insisted they start the day there. "Awkward and hot." Was his review. They spent the rest of the morning playing disc golf, and then brought their packed lunch to Lloyd Lake, consciously and ironically choosing to find a spot near the Portals of the Past. After getting pictures together there and posting them to Instagram, they settled in to relax and eat.

After their meal, Jiya leaned back against Rufus. He took out Liu Cixin's latest sci-fi book in translation, and settled in to read. She had Now: The Physics of Time set beside her. She'd read the first several chapters already, and was content at the moment just to soak in the sunlight and peace.

Rufus looked down at her. "Aren't we tempting fate a bit with all this?" He gestured at the elaborate portico near them, known as the Portals of the Past. Another couple was perched near the steps now, balancing their phone on a selfie stick dangerously close to the water. Jiya laughed. Rufus smiled and went on, "You learn anything new from Dr. Muller on the nature of time?"

Jiya flopped over, her head on his lap, and smiled up at him. "He says that the as the universe expands, time expands as well. And since the universe hasn't expanded to where it goes in the future yet, the future does not yet exist. He talks about the present as the crest of a tide that we're riding forward."

"Well, that might explain why we can't go forward in time?"

She reached up to where he held his book, fiddling idly with his watch. "But this would also mean that the universe is no longer where it was when we experienced the past, so therefore time travel to the future and the past would be equally impossible." Rufus put his book down and took her hand. "Which we've—rather, you and Anthony, have proved is patently untrue."

"As you've learned all too well." He gave her a worried look.

Jiya smiled at him. "I'm fine, really. I haven't had a fit in weeks." She squeezed his hand and went on. "It may be that part of the problem is our conception of what space is. Every point in space is expanding away from every other point in space, around some center that we can't conceive of."

"Like the 2 dimensional person trying to imagine a 3 dimensional world."

"Yup. And yet we go into the past all the time, so we're from the future of those folks we interact with. It seems like the flow of time may be more a matter of perception, like layers of an onion or rings in a tree. What happened in the past is still there, but maybe when you're riding the crest, like he says, you can't see forward, only back."

"But," Rufus looked reluctant to say this, "that still doesn't account for the many different timelines. How can the past co-exist with the present and yet the events be fluid and changeable?"

"Maybe all the different timelines are coexistent, like a matrix. It goes back to that conceptual problem, we need math and theoretical physics to describe the shapes the universe makes, but we can't perceive it with our normal senses." They looked at one another.

Rufus said, "And this is what we choose to do on our day off." He mumbled something about "being made for each other," and leaned down to give her a kiss. She closed her eyes and felt a rush of tenderness and desire that still felt brand new. She opened her eyes as he raised his head again and saw look of bemused wonder on Rufus' face.

They sat staring dopily into each others' eyes for a few moments, then laughed and broke eye contact. Jiya settled back down and opened up her book, giving a satisfied glance up at Rufus as he went back to reading his. He had a very wide smile on his face and his eyes still looked faraway. She sighed and said, "I hope Lucy and Wyatt are having a good day, too."

Rufus' eyes took on some worry. He shook his head and said uncertainly. "Yeah, I wish them luck."

Jiya put her book down on her chest. "Wait, what do you mean by that?"

Rufus looked guilty and kept on reading, "Nothing. Just hoping they enjoy themselves."

Jiya sat up. "You are a terrible liar. What do you know?"

Rufus put his book down, too, and looked at her squarely. "Nothing I can talk about. I gave my word."

Jiya shook her hands in the air and smiled broadly. "Oh, this is great! I did, too, but only if you didn't know already. What did Wyatt tell you? Did he tell you more about the kiss?"

Rufus looked stunned. "So you know about that?"

"Well, she didn't tell me much, just that it happened..."

"How long have you known?"

Jiya looked at him confused. "Wait, how long could I have known, it just happened last night! Wait," She looked at him incredulously. "No. You have more to tell me don't you?"

Rufus put his face in his hand and nodded. "Wyatt is going to kill me."

A/N: Apologies to any physicists or cosmologists for any errors or bad technobabble you may notice here. Tried to keep it w/in contemporary thoughts, but I'm no expert. :) All errors are mine, Rufus & Jiya of course would be up on the most correct & cutting edge science, a la exotic matter.

Also, hurrah Timeless fandom & makers! #TimelessUncancelled!

25 May 2017: per a summary of Shawn Ryan's AMA I see that multiple timeless not in canon. Ah well! This is all speculation on the Time Team's part, anyway. #timemachineproblems