\documentclass[tikz,border=5pt]{standalone}
\usepackage{amsmath, amssymb, tikz, color, geometry}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\geometry{margin=1in}
\begin{document}
\begin{tikzpicture}[x=0.75pt,y=0.75pt,yscale=-0.8,xscale=0.8]
\draw (350,323) -- (653,41) -- (350,41) -- cycle ;
\draw (351,175) .. controls (400,179) and (531,115) .. (653,41) ;
\draw [color={rgb, 255:red, 126; green, 211; blue, 33 } ,draw opacity=1 ][line width=1.5] (32,323) -- (32.99,25) ;
\draw [shift={(33,22)}, rotate = 90.19] [color={rgb, 255:red, 126; green, 211; blue, 33 } ,draw opacity=1 ][line width=1.5] (14.21,-4.28) .. controls (9.04,-1.82) and (4.3,-0.39) .. (0,0) .. controls (4.3,0.39) and (9.04,1.82) .. (14.21,4.28) ;
\draw [color={rgb, 255:red, 208; green, 2; blue, 27 } ,draw opacity=1 ] (350,39.5) .. controls (351.67,37.83) and (353.33,37.83) .. (355,39.5) .. controls (356.67,41.17) and (358.33,41.17) .. (360,39.5) .. controls (361.67,37.83) and (363.33,37.83) .. (365,39.5) .. controls (366.67,41.17) and (368.33,41.17) .. (370,39.5) .. controls (371.67,37.83) and (373.33,37.83) .. (375,39.5) .. controls (376.67,41.17) and (378.33,41.17) .. (380,39.5) .. controls (381.67,37.83) and (383.33,37.83) .. (385,39.5) .. controls (386.67,41.17) and (388.33,41.17) .. (390,39.5) .. controls (391.67,37.83) and (393.33,37.83) .. (395,39.5) .. controls (396.67,41.17) and (398.33,41.17) .. (400,39.5) .. controls (401.67,37.83) and (403.33,37.83) .. (405,39.5) .. controls (406.67,41.17) and (408.33,41.17) .. (410,39.5) .. controls (411.67,37.83) and (413.33,37.83) .. (415,39.5) .. controls (416.67,41.17) and (418.33,41.17) .. (420,39.5) .. controls (421.67,37.83) and (423.33,37.83) .. (425,39.5) .. controls (426.67,41.17) and (428.33,41.17) .. (430,39.5) .. controls (431.67,37.83) and (433.33,37.83) .. (435,39.5) .. controls (436.67,41.17) and (438.33,41.17) .. (440,39.5) .. controls (441.67,37.83) and (443.33,37.83) .. (445,39.5) .. controls (446.67,41.17) and (448.33,41.17) .. (450,39.5) .. controls (451.67,37.83) and (453.33,37.83) .. (455,39.5) .. controls (456.67,41.17) and (458.33,41.17) .. (460,39.5) .. controls (461.67,37.83) and (463.33,37.83) .. (465,39.5) .. controls (466.67,41.17) and (468.33,41.17) .. (470,39.5) .. controls (471.67,37.83) and (473.33,37.83) .. (475,39.5) .. controls (476.67,41.17) and (478.33,41.17) .. (480,39.5) .. controls (481.67,37.83) and (483.33,37.83) .. (485,39.5) .. controls (486.67,41.17) and (488.33,41.17) .. (490,39.5) .. controls (491.67,37.83) and (493.33,37.83) .. (495,39.5) .. controls (496.67,41.17) and (498.33,41.17) .. (500,39.5) .. controls (501.67,37.83) and (503.33,37.83) .. (505,39.5) .. controls (506.67,41.17) and (508.33,41.17) .. (510,39.5) .. controls (511.67,37.83) and (513.33,37.83) .. (515,39.5) .. controls (516.67,41.17) and (518.33,41.17) .. (520,39.5) .. controls (521.67,37.83) and (523.33,37.83) .. (525,39.5) .. controls (526.67,41.17) and (528.33,41.17) .. (530,39.5) .. controls (531.67,37.83) and (533.33,37.83) .. (535,39.5) .. controls (536.67,41.17) and (538.33,41.17) .. (540,39.5) .. controls (541.67,37.83) and (543.33,37.83) .. (545,39.5) .. controls (546.67,41.17) and (548.33,41.17) .. (550,39.5) .. controls (551.67,37.83) and (553.33,37.83) .. (555,39.5) .. controls (556.67,41.17) and (558.33,41.17) .. (560,39.5) .. controls (561.67,37.83) and (563.33,37.83) .. (565,39.5) .. controls (566.67,41.17) and (568.33,41.17) .. (570,39.5) .. controls (571.67,37.83) and (573.33,37.83) .. (575,39.5) .. controls (576.67,41.17) and (578.33,41.17) .. (580,39.5) .. controls (581.67,37.83) and (583.33,37.83) .. (585,39.5) .. controls (586.67,41.17) and (588.33,41.17) .. (590,39.5) .. controls (591.67,37.83) and (593.33,37.83) .. (595,39.5) .. controls (596.67,41.17) and (598.33,41.17) .. (600,39.5) .. controls (601.67,37.83) and (603.33,37.83) .. (605,39.5) .. controls (606.67,41.17) and (608.33,41.17) .. (610,39.5) .. controls (611.67,37.83) and (613.33,37.83) .. (615,39.5) .. controls (616.67,41.17) and (618.33,41.17) .. (620,39.5) .. controls (621.67,37.83) and (623.33,37.83) .. (625,39.5) .. controls (626.67,41.17) and (628.33,41.17) .. (630,39.5) .. controls (631.67,37.83) and (633.33,37.83) .. (635,39.5) .. controls (636.67,41.17) and (638.33,41.17) .. (640,39.5) .. controls (641.67,37.83) and (643.33,37.83) .. (645,39.5) .. controls (646.67,41.17) and (648.33,41.17) .. (650,39.5) -- (653,39.5) -- (653,39.5)(350,42.5) .. controls (351.67,40.83) and (353.33,40.83) .. (355,42.5) .. controls (356.67,44.17) and (358.33,44.17) .. (360,42.5) .. controls (361.67,40.83) and (363.33,40.83) .. (365,42.5) .. controls (366.67,44.17) and (368.33,44.17) .. (370,42.5) .. controls (371.67,40.83) and (373.33,40.83) .. (375,42.5) .. controls (376.67,44.17) and (378.33,44.17) .. (380,42.5) .. controls (381.67,40.83) and (383.33,40.83) .. (385,42.5) .. controls (386.67,44.17) and (388.33,44.17) .. (390,42.5) .. controls (391.67,40.83) and (393.33,40.83) .. (395,42.5) .. controls (396.67,44.17) and (398.33,44.17) .. (400,42.5) .. controls (401.67,40.83) and (403.33,40.83) .. (405,42.5) .. controls (406.67,44.17) and (408.33,44.17) .. (410,42.5) .. controls (411.67,40.83) and (413.33,40.83) .. (415,42.5) .. controls (416.67,44.17) and (418.33,44.17) .. (420,42.5) .. controls (421.67,40.83) and (423.33,40.83) .. (425,42.5) .. controls (426.67,44.17) and (428.33,44.17) .. (430,42.5) .. controls (431.67,40.83) and (433.33,40.83) .. (435,42.5) .. controls (436.67,44.17) and (438.33,44.17) .. (440,42.5) .. controls (441.67,40.83) and (443.33,40.83) .. (445,42.5) .. controls (446.67,44.17) and (448.33,44.17) .. (450,42.5) .. controls (451.67,40.83) and (453.33,40.83) .. (455,42.5) .. controls (456.67,44.17) and (458.33,44.17) .. (460,42.5) .. controls (461.67,40.83) and (463.33,40.83) .. (465,42.5) .. controls (466.67,44.17) and (468.33,44.17) .. (470,42.5) .. controls (471.67,40.83) and (473.33,40.83) .. (475,42.5) .. controls (476.67,44.17) and (478.33,44.17) .. (480,42.5) .. controls (481.67,40.83) and (483.33,40.83) .. (485,42.5) .. controls (486.67,44.17) and (488.33,44.17) .. (490,42.5) .. controls (491.67,40.83) and (493.33,40.83) .. (495,42.5) .. controls (496.67,44.17) and (498.33,44.17) .. (500,42.5) .. controls (501.67,40.83) and (503.33,40.83) .. (505,42.5) .. controls (506.67,44.17) and (508.33,44.17) .. (510,42.5) .. controls (511.67,40.83) and (513.33,40.83) .. (515,42.5) .. controls (516.67,44.17) and (518.33,44.17) .. (520,42.5) .. controls (521.67,40.83) and (523.33,40.83) .. (525,42.5) .. controls (526.67,44.17) and (528.33,44.17) .. (530,42.5) .. controls (531.67,40.83) and (533.33,40.83) .. (535,42.5) .. controls (536.67,44.17) and (538.33,44.17) .. (540,42.5) .. controls (541.67,40.83) and (543.33,40.83) .. (545,42.5) .. controls (546.67,44.17) and (548.33,44.17) .. (550,42.5) .. controls (551.67,40.83) and (553.33,40.83) .. (555,42.5) .. controls (556.67,44.17) and (558.33,44.17) .. (560,42.5) .. controls (561.67,40.83) and (563.33,40.83) .. (565,42.5) .. controls (566.67,44.17) and (568.33,44.17) .. (570,42.5) .. controls (571.67,40.83) and (573.33,40.83) .. (575,42.5) .. controls (576.67,44.17) and (578.33,44.17) .. (580,42.5) .. controls (581.67,40.83) and (583.33,40.83) .. (585,42.5) .. controls (586.67,44.17) and (588.33,44.17) .. (590,42.5) .. controls (591.67,40.83) and (593.33,40.83) .. (595,42.5) .. controls (596.67,44.17) and (598.33,44.17) .. (600,42.5) .. controls (601.67,40.83) and (603.33,40.83) .. (605,42.5) .. controls (606.67,44.17) and (608.33,44.17) .. (610,42.5) .. controls (611.67,40.83) and (613.33,40.83) .. (615,42.5) .. controls (616.67,44.17) and (618.33,44.17) .. (620,42.5) .. controls (621.67,40.83) and (623.33,40.83) .. (625,42.5) .. controls (626.67,44.17) and (628.33,44.17) .. (630,42.5) .. controls (631.67,40.83) and (633.33,40.83) .. (635,42.5) .. controls (636.67,44.17) and (638.33,44.17) .. (640,42.5) .. controls (641.67,37.83) and (643.33,37.83) .. (645,42.5) .. controls (646.67,44.17) and (648.33,44.17) .. (650,42.5) -- (653,42.5) -- (653,42.5) ;
\draw (343,175) -- (287,175) ;
\draw [shift={(285,175)}, rotate = 360] [color={rgb, 255:red, 0; green, 0; blue, 0 } ][line width=0.75] (10.93,-3.29) .. controls (6.95,-1.4) and (3.31,-0.3) .. (0,0) .. controls (3.31,0.3) and (6.95,1.4) .. (10.93,3.29) ;
\draw (361,41) -- (305,41) ;
\draw [shift={(303,41)}, rotate = 360] [color={rgb, 255:red, 0; green, 0; blue, 0 } ][line width=0.75] (10.93,-3.29) .. controls (6.95,-1.4) and (3.31,-0.3) .. (0,0) .. controls (3.31,0.3) and (6.95,1.4) .. (10.93,3.29) ;
\draw (475.73,214.18) node [anchor=north west][inner sep=0.75pt] [rotate=-315] [align=left] {past infinity};
\draw (368,186) node [anchor=north west][inner sep=0.75pt] [color={rgb, 255:red, 74; green, 144; blue, 226 } ,opacity=1 ] [align=left] {Phase II:};
\draw (374,87.4) node [anchor=north west][inner sep=0.75pt] [color={rgb, 255:red, 208; green, 2; blue, 27 } ,opacity=1 ] {$\frac{d|\dot{a} |}{dt} < 0$};
\draw (376,60) node [anchor=north west][inner sep=0.75pt] [color={rgb, 255:red, 208; green, 2; blue, 27 } ,opacity=1 ] [align=left] {Phase I:};
\draw (9.5,197.5) node [anchor=north west][inner sep=0.75pt] [color={rgb, 255:red, 126; green, 211; blue, 33 } ,opacity=1 ,rotate=-270] [align=left] {time};
\draw (368,213.4) node [anchor=north west][inner sep=0.75pt] [color={rgb, 255:red, 74; green, 144; blue, 226 } ,opacity=1 ] {$\frac{d|\dot{a} |}{dt} \geq 0$};
\draw (157,156) node [anchor=north west][inner sep=0.75pt] [align=left] {\begin{minipage}[lt]{90.04pt}\setlength\topsep{0pt}
Particle production \\with $\displaystyle k\sim H$
\end{minipage}};
\draw (176,284) node [anchor=north west][inner sep=0.75pt] [align=left] {Initial vacuum};
\draw (65,284.4) node [anchor=north west][inner sep=0.75pt] {$t\rightarrow -\infty :$};
\draw (71,161.4) node [anchor=north west][inner sep=0.75pt] {$t=t_{*} :$};
\draw (64,32.4) node [anchor=north west][inner sep=0.75pt] {$t=t_{*} +\Delta t:$};
\draw (156,30) node [anchor=north west][inner sep=0.75pt] [align=left] {\begin{minipage}[lt]{97.4pt}\setlength\topsep{0pt}
Blue-shifted particles\\are trans-Planckian
\end{minipage}};
\end{tikzpicture}
\end{document}